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1.	Bos, R., et al. (author) Retention of bacteria on a substratum surface with micro-patterned hydrophobicity 2000 In: FEMS Microbiology Letters. - : Oxford University Press (OUP). - 1574-6968 .- 0378-1097. ; 189:2, s. 311-315 Journal article (peer-reviewed)abstract Bacteria adhere to almost any surface, despite continuing arguments about the importance of physico-chemical properties of substratum surfaces, such as hydrophobicity and charge in biofilm formation. Nevertheless, in vivo biofilm formation on teeth and also on voice prostheses in laryngectomized patients is less on hydrophobic than on hydrophilic surfaces. With the aid of micro-patterned surfaces consisting of 10-mu m wide hydrophobic lines separated by 20-mu m wide hydrophilic spacings, we demonstrate here, For the first time in one and the same experiment, that bacteria do not have a strong preference for adhesion to hydrophobic or hydrophilic surfaces. Upon challenging the adhering bacteria, after deposition in a parallel plate flow chamber, with a high detachment force, however, bacteria were easily wiped-off hydrophobic lines, most notably when these lines were oriented parallel to the direction of flow. Adhering bacteria detached slightly less from the hydrophilic spacings in between, but preferentially accumulated adhering on the hydrophilic regions close to the interface between the hydrophilic spacings and hydrophobic lines. It is concluded that substratum hydrophobicity is a major determinant of bacterial retention while it hardly influences bacterial adhesion.
2.	Pedersen, Karsten, 1952 (author) Exploration of deep intraterrestrial microbial life:current perspectives 2000 In: FEMS Microbiology Letters. - : Oxford University Press (OUP). - 0378-1097 .- 1574-6968. ; 185:1, s. 9-16 Research review (peer-reviewed)
3.	Throne-Holst, Mimmi, et al. (author) The Bacillus subtilis ctaB paralogue, yjdK, can complement the heme A synthesis deficiency of a CtaB-deficient mutant 2000 In: FEMS Microbiology Letters. - : Oxford University Press (OUP). - 1574-6968 .- 0378-1097. ; 183, s. 247-251 Journal article (peer-reviewed)abstract Heme A is a prosthetic group in many respiratory oxidases. It is synthesised from heme B (protoheme IX) with heme O as an intermediate. In Bacillus subtilis two genes required for heme A synthesis, ctaA and ctaB, have been identified. CtaB is the heme O synthase and CtaA is involved in the conversion of heme O to heme A. A ctaB paralogue, yjdK, has been identified through the B. subtilis genome sequencing project. In this study we show that when carried on a low copy number plasmid, the yjdK gene can complement a ctaB deletion mutant with respect to heme A synthesis. Our results indicate that YjdK has heme O synthase activity. We therefore suggest that yjdK be renamed as ctaO.
4.	Bontempi, EJ, et al. (author) The tyrosine aminotransferase from Trypanosoma rangeli : sequence andgenomic characterization 2000 In: FEMS Microbiology Letters. - : Oxford University Press (OUP). - 0378-1097 .- 1574-6968. ; 189:2, s. 253-257 Journal article (peer-reviewed)abstract The complete sequence and genomic characterization of the tyrosine aminotransferase (TAT) gene from Trypanosoma rangeli is reported. The gene was found to be organized in a tandem multicopy gene array. A homologous mRNA species (2.5 kb) was identified in the epimastigote form of the parasite. From the deduced amino acid sequence, the gene encodes a protein of 420 amino acids with a predicted molecular mass of 46.4 kDa and a theoretical pI of 6.23. A high sequence identity was found with the Trypanosoma cruzi, human and rat enzymes. All the essential residues for TAT enzymatic activity are conserved, as well as a pyridoxal-phosphate attachment site typical of class-I aminotransferases. The recombinant enzyme was recognized by a monoclonal antibody against the T. cruzi enzyme. Additionally, the recombinant protein showed enzymatic activity when incubated with L-tyrosine and 2-oxoglutaric acid as substrates.
5.	Graslund, S., et al. (author) Single-vector three-frame expression systems for affinity-tagged proteins 2002 In: FEMS Microbiology Letters. - : Oxford University Press (OUP). - 0378-1097 .- 1574-6968. ; 215:1, s. 139-147 Journal article (peer-reviewed)abstract An effort is presented to create expression vectors which would allow expression of an inserted gene fragment in three reading frames in a single vector from a single promoter but with three separate ribosome binding sites (RBS). Each expression frame would generate an in-frame fusion with an affinity tag to allow efficient recovery of the produced fusion proteins. In the first generation vector, three identical polyhistidyl tags (His(6)) were used as affinity tags for the three expression frames. In the second generation vector, three different tags, an albumin binding domain derived from streptococcal protein G, an IgG binding Staphylococcus aureus protein A-derived domain (Z) and a His(6) tag, were employed to allow frame-specific affinity recovery. To evaluate the systems, model genes have been inserted in three different frames in both vectors. The first vector was demonstrated to produce fusion proteins in all three frames, whereas for the second, with a much wider spacing between the RBSs and affinity tags, expression could only be demonstrated from the first two translational start sites. For both systems, the first translation start was found to be significantly favored over the others. Nevertheless, we believe that the presented results represent the first successful attempt to create single-vector three-frame expression systems, a concept that could become valuable in future combined cloning-expression vectors.
6.	Hansson, M., et al. (author) General expression vectors for Staphylococcus carnosus enabled efficient production of the outer membrane protein A of Klebsiella pneumoniae 2002 In: FEMS Microbiology Letters. - : Oxford University Press (OUP). - 0378-1097 .- 1574-6968. ; 210:2, s. 263-270 Journal article (peer-reviewed)abstract General expression vectors, designed for intracellular expression or secretion of recombinant proteins in the non-pathogenic Staphylococcus carnosus, were constructed. Both vector systems encode two different affinity tags, an upstream albumin binding protein and a downstream hexahistidyl peptide, and are furnished with cleavage sites for two site-specific proteases for optional affinity tag removal. To evaluate the novel vectors, the gene encoding the outer membrane protein A (OmpA) of Klebsiella pneumoniae was introduced into the vectors. Efficient production was demonstrated in both systems, although, as expected for OmpA fusions, somewhat better intracellularly, and the fusion proteins could be recovered as full-length products by affinity chromatography.
7.	Kamalakannan, V, et al. (author) Identification of a novel mycobacterial transcriptional regulator and its involvement in growth rate dependence and stringent control 2002 In: FEMS microbiology letters. - : Oxford University Press (OUP). - 0378-1097 .- 1574-6968. ; 209:2, s. 261-266 Journal article (peer-reviewed)
8.	Kuttuva, Gunaratna R., et al. (author) Peptide-mediated delivery of green fluorescent protein into yeasts and bacteria 2002 In: FEMS Microbiology Letters. - : Oxford University Press (OUP). - 0378-1097 .- 1574-6968. ; 215:2, s. 267-272 Journal article (peer-reviewed)abstract Stringent microbial cell barriers limit the application of many substances in research and therapeutics. Carrier peptides that penetrate or translocate across cell membranes may help overcome this problem. To assess peptide-mediated delivery into two yeast and three bacterial species, a range of cell penetrating and signal peptide sequences were fused to green fluorescent protein (GFP), expressed in Escherichia coli, partially purified and incubated with growing cells. Fluorescence microscopy indicated several peptides that mediated delivery. In particular, VLTNENPFSDP efficiently delivered GFP into Candida albicans and Staphylococcus aureus, while YKKSNNPFSD was most efficient for Bacillus subtilis and CFFKDEL for Escherichia coli. Carrier peptides may improve delivery of certain large molecular mass molecules into microorganisms for research and therapeutic applications.
9.	Lerm, Maria, et al. (author) Bacterial protein toxins targeting rho GTPases 2000 In: FEMS Microbiology Letters. - : Wiley-Blackwell. - 0378-1097 .- 1574-6968. ; 188:1, s. 1-6 Journal article (peer-reviewed)abstract Several bacterial protein toxins target eukaryotic cells by modulating the functions of Rho GTPases that are involved in various signal processes and in the regulation of the actin cytoskeleton. The toxins inhibit Rho functions by ADP-ribosylation or glucosylation and activate them by deamidation and transglutamination. New findings indicate that the GTPases are also targeted by various 'injected' toxins which are introduced into the eukaryotic cells by the type-III secretion system. The injected toxins do not covalently modify Rho GTPases, but manipulate their regulatory GTPase cycle by acting as GTPase-activating proteins or guanine nucleotide exchange factors.
10.	Svard, SG, et al. (author) Giardia lamblia -- a model organism for eukaryotic cell differentiation 2003 In: FEMS microbiology letters. - : Oxford University Press (OUP). - 0378-1097 .- 1574-6968. ; 218:1, s. 3-7 Journal article (peer-reviewed)
11.	Svensäter, Gunnel, et al. (author) Protein expression by planktonic and biofilm cells of Streptococcus mutans 2001 In: FEMS Microbiology Letters. - : Elsevier. - 0378-1097 .- 1574-6968. ; 205:1, s. 139-146 Journal article (peer-reviewed)abstract Streptococcus mutans, a major causal agent of dental caries, functions in nature as a component of a biofilm on teeth (dental plaque) and yet very little information is available on the physiology of the organism in such surface-associated communities. As a consequence, we undertook to examine the synthesis of proteins by planktonic and biofilm cells growing in a biofilm chemostat at pH 7.5 at a dilution rate of 0.1 h(-1) (mean generation time=7 h). Cells were incubated with (14)C-labelled amino acids, the proteins extracted and separated by two-dimensional electrophoresis followed by autoradiography and computer-assisted image analysis. Of 694 proteins analysed, 57 proteins were enhanced 1.3-fold or greater in biofilm cells compared to planktonic cells with 13 only expressed in sessile cells. Diminished protein expression was observed with 78 proteins, nine of which were not expressed in biofilm cells. The identification of enhanced and diminished proteins by mass spectrometry and computer-assisted protein sequence analysis revealed that, in general, glycolytic enzymes involved in acid formation were repressed in biofilm cells, while biosynthetic processes were enhanced. The results show that biofilm cells possess novel proteins, of as yet unknown function, that are not present in planktonic cells.
12.	Westberg, J., et al. (author) ISMmy1, a novel insertion sequence of Mycoplasma mycoides subsp mycoides small colony type 2002 In: FEMS Microbiology Letters. - : Oxford University Press (OUP). - 0378-1097 .- 1574-6968. ; 208:2, s. 207-213 Journal article (peer-reviewed)abstract A new insertion sequence, ISMmy1, has been identified in the bovine pathogen Mycoplasma mycoides subsp. mycoides biotype small colony MmymySC. The occurrence of ISMmy1 in 15 MmymySC strains and 12 other mycoplasmas was examined by Southern blotting. All MmymySC strains showed identical hybridisation patterns except for the type strain PG11, the vaccine strain T1Sr49, and the strain Afade, which all had unique patterns. ISMmy1-like sequences were also found in the bovine pathogen Mycoplasma bovis strain Donetta(T) while mycoplasmas that are phylogenetically closer to MmymySC lack ISMmy1. This observation suggests horizontal transfer between MmymySC and M. bovis.
13.	Zeng, Qing-Yin, et al. (author) Extensive set of mitochondrial LSU rDNA-based oligonucleotide probes for the detection of common airborne fungi. 2004 In: FEMS Microbiology Letters. - : Oxford University Press (OUP). - 0378-1097 .- 1574-6968. ; 237:1, s. 79-87 Journal article (peer-reviewed)abstract Fungi exist in every indoor and outdoor environment. Many fungi are toxigenic or pathogens that may cause various public health concerns. Rapid and accurate detection and identification of fungi require specific markers. In this study, partial mitochondrial large subunit rDNA was amplified and sequenced from 32 fungal strains representing 31 species from 14 genera. Based on the sequence variation pattern, 26 oligonucleotide probes were designed for their discrimination. The specificity of the probes was evaluated through homology search against GenBank database and hybridization examination on 38 fungal strains. The 26 probes were verified as highly specific to 20 fungal species. A two-step detection procedure through PCR followed by probe hybridization gave ten-fold increase in detection sensitivity than single-step PCR assay and would be a practical approach for environmental sample screening. The probes developed in this study can be applied in clinical diagnosis and environmental monitoring of fungal agents.
14.	Mohapatra, Anasuya, et al. (author) A hydrogen-evolving enzyme is present in Frankia sp. R43 2004 In: FEMS Microbiology Letters. - Amsterdam : Elsevier/North-Holland. - 0378-1097 .- 1574-6968. ; 236:2, s. 235-240 Journal article (peer-reviewed)abstract The ability to evolve hydrogen using methyl viologen as an electron donor was assayed in the nitrogen-fixing actinomycetes Frankia sp. R43 and Frankia sp. KB5. To further examine the nature of hydrogen-evolving enzymes that may be present in these organisms immunological studies were performed. Under anaerobic conditions (both nitrogen-limiting and nitrogen-containing) Frankia sp. R43 but not Frankia sp. KB5 evolved hydrogen,which was not linked to NAD-reducing activity. Immunological analysis of total protein from Frankia sp. R43 and Frankia sp. KB5 using an antiserum raised against Ralstonia eutropha HoxF, recognized an antigen in Frankia sp. R43 but not in Frankia sp. KB5. Immunogold labeling using antibodies raised against the R. eutropha HoxH recognized sites in both hyphae and vesicles of Frankia sp. R43, but not in Frankia sp. KB5. Based on these physiological and immunological findings, we conclude that Frankia sp. R43 has a hydrogen-evolving hydrogenase.
15.	Apoga, D, et al. (author) Analysis of proteins in the extracellular matrix of the plant pathogenic fungus Bipolaris sorokiniana using 2-D gel electrophoresis and MS/MS 2001 In: FEMS Microbiology Letters. - 1574-6968. ; 197:2, s. 145-150 Journal article (peer-reviewed)abstract A method was developed for isolating and sequencing proteins present in the extracellular matrix (ECM) of germlings and hyphae of filamentous fungi, Surface proteins of the cereal pathogen Bipolaris sorokiniana were labelled with a membrane impermeable biotinylating agent and extracted using a glycine-HCl buffer. Extracted proteins were purified by affinity binding to streptavidin-conjugated magnetic beads or by two-dimensional gel electrophoresis. Four of the biotinylated proteins from the ECM of B. sorokiniana were isolated, in gel digested with trypsin and partly sequenced by tandem mass spectrometry. No significant sequence similarities to proteins in databases were obtained. (C) 2001 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights, reserved.
16.	Asiegbu, F.O., et al. (author) Isolation of a novel antimicrobal peptide gene (Sp-AMP) homologue from Pinus sylvestris (Scots pine) following infection with the root rot fungus Heterobasidion annosum 2003 In: FEMS Microbiology Letters. - 0378-1097 .- 1574-6968. ; 228:1, s. 27-31 Journal article (peer-reviewed)abstract A new family of antimicrobial peptide homologues termed Sp-Amp has been discovered in Pinus sylvestris (Scots pine). This is the first report of such proteins to be characterized in a conifer species. Sp-AMP1 was identified in a substructured cDNA library of root tissue infected with the root rot fungus Heterobasidion annosum and encodes a mature peptide of 79 amino acid residues. Three additional members of the Sp-AMP family (Sp-AMPs 2–4) encode cysteine-rich proteins of 105 amino acids, each containing an N-terminal region with a probable cleavage signal sequence. Northern analysis confirmed that Sp-AMP expression is elevated in Scots pine roots upon infection with H. annosum. These peptides share 64% amino acid identity with a mature protein from Macadamia integrifolia (MiAMP1), which allowed us to build a homology model for preliminary analysis. Southern analyses further confirmed that several copies of the gene are present in the Scots pine genome. The potential significance of Sp-AMP in the H. annosum–conifer pathosystem is discussed.
17.	Collin, Mattias, et al. (author) Identification of conditionally expressed genes in Streptococcus pyogenes using RNA fingerprinting 2001 In: FEMS Microbiology Letters. - 1574-6968. ; 196:2, s. 123-127 Journal article (peer-reviewed)abstract RNA fingerprinting using arbitrarily primed reverse transcription-polymerase chain reaction was employed on isolated RNA from Streptococcus pyogenes bacteria in order to identify genes that were regulated in response to environmental changes. When S. pyogenes was cultured under glucose-rich growth conditions a number of transcriptionally up-regulated products were identified, cloned and sequenced. Using the Streptococcal Genome Sequencing Project database and similarity searches against the GenBank database the corresponding genes encoding enzyme IIB and IIC component of a putative phosphotransferase system were identified. Thus, we show that RNA fingerprinting could be a useful tool to identify unknown genes in S. pyogenes that are expressed under certain environmental conditions.
18.	Diez, A A, et al. (author) The Escherichia coli ftsK1 mutation attenuates the induction of sigma(s)-dependent genes upon transition to stationary phase 2002 In: FEMS Microbiology Letters. - 1574-6968. ; 206:1, s. 19-23 Journal article (peer-reviewed)abstract A mutation in the cell division gene ftsK causes super-induction of sigma(70)-dependent stress defense genes, such as uspA, during entry of cells into stationary phase. In contrast, we report here that stationary phase induction of sigma(S)-dependent genes, uspB and cfa, is attenuated and that sigma(S) accumulates at a lower rate in ftsK1 cells. Ectopic overexpression of rpoS restored induction of the rpoS regulon in the ftsK mutant, as did a deletion in the recA gene. Thus, a mutation in the cell division gene,ftsY, uncouples the otherwise coordinated induction of sigma(S)-dependent genes and the universal stress response gene, uspA, during entry into stationary phase. (C) 2002 Federation of European Microbiological Societies, Published by Elsevier Science B.V. All rights reserved.
19.	Fredlund, Elisabeth, et al. (author) Influence of ethyl acetate production and ploidy on the anti-mould activity of Pichia anomala 2004 In: FEMS Microbiology Letters. - : Elsevier. - 0378-1097 .- 1574-6968. ; 238:1, s. 133-137 Journal article (peer-reviewed)abstract A diploid and a haploid strain of Pichia anomala were tested for their biocontrol ability against the spoilage mould Penicillium roqueforti in glass tubes filled with grain at two water activities (a(w)). At a(w) 0.98, the two yeast strains grew and inhibited mould growth equally well and showed similar patterns of ethyl acetate production, reaching maximum values of 10-14 mug ml(-1) headspace. At a(w) 0.95, both growth and biocontrol performance of the haploid strain were reduced. Ethyl acetate formation was also substantially reduced, with maximum headspace concentrations of 4 mug ml(-1). We conclude that ethyl acetate is a major component of the anti-mould activity. The inhibitory effect of ethyl acetate was confirmed in a bioassay where the pure compound reduced biomass production of P. roqueforti.
20.	Grahn, Niclas, et al. (author) Identification of mixed bacterial DNA contamination in broad-range PCR amplification of 16S rDNA V1 and V3 variable regions by pyrosequencing of cloned amplicons 2003 In: FEMS Microbiology Letters. - 0378-1097 .- 1574-6968. ; 219:1, s. 87-91 Journal article (peer-reviewed)abstract Using a sensitive and rapid method combining broad-range PCR amplification of bacterial 16S rDNA fragments and pyrosequencing for detection, identification and typing, we have found contaminating bacterial DNA in our reagents used for PCR. Identified bacteria are the water-borne bacterial genera Pseudomonas, Stenotrophomonas, Xanthomonas, Ralstonia and Bacillus. Our results are in concordance with recent reports of contaminated industrial water systems. In light of this conclusion, we believe that there is a need for increased awareness of possible contamination in uncertified widely used molecular biology reagents, including ultra-pure water. Since sequence-based 16S rDNA techniques are used in a variety of settings for bacterial typing and the characterization of microbial communities, we feel that future certification of molecular biology reagents, as free of nucleic acids, would be advantageous. ⌐ 2002 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.
21.	Gustafsson, Mattias, et al. (author) A novel diffusible substance can overcome the apparent AbrB repression of the Bacillus subtilis fatR promoter 2001 In: FEMS Microbiology Letters. - 1574-6968. ; 199:2, s. 197-202 Journal article (peer-reviewed)abstract In this work we present evidence for a novel diffusible extracellular factor that modulates gene expression in Bacillus subtilis. The factor was found when studying the regulation of the fatR-cyp102A3 operon. In a Spo0A(-) mutant expression of the fatR-cyp102A3 operon was almost abolished. The fatR-cyp102A3 expression defect of a Spo0A(-) mutant could be overcome either by a mutation in the abrB gene or by a diffusible substance excreted by wild-type, abrB mutant and abrB-spo0A double mutant strains.
22.	Kadioglu, Aras, et al. (author) Use of green fluorescent protein in visualisation of pneumococcal invasion of broncho-epithelial cells in vivo 2001 In: FEMS Microbiology Letters. - 1574-6968. ; 194:1, s. 105-110 Journal article (peer-reviewed)abstract The pneumococcus is the principle cause of bacterial pneumonia and also a major cause of bacterial meningitis. The mechanisms and sites of pneumococcal adherence and invasion of the respiratory tract in vivo are not clear however. We have made pneumococci expressing green fluorescent protein (GFP) and used it to trace pneumococcal adherence and invasion in vivo. By using GFP pneumococci we have shown bacterial adherence and invasion of broncho-epithelial cells in vivo by 4 h post-infection, with increases in pneumococcal invasiveness by 24 h. Using confocal image analysis we have shown varying levels of pneumococcal penetration and internalisation into host cells, as well as translocation through epithelial layers. To our knowledge this is the first report of pneumococcal invasion and cellular translocation in vivo.
23.	Lai, Xin-He, et al. (author) Francisella strains express hemolysins of distinct characteristics 2003 In: FEMS Microbiology Letters. - : Elsevier. - 0378-1097 .- 1574-6968. ; 224:1, s. 91-95 Journal article (peer-reviewed)abstract Historically, Francisella strains have been described as nonhemolytic. In this study, we show by use of solid and liquid hemolysis assays that some Francisella strains have hemolytic properties. The Francisella novicida type strain U112 is hemolytic to horse erythrocytes and Francisella philomiragia type strain FSC144 is hemolytic towards both human and horse erythrocytes. The F. novicida strain U112 released a protein (novilysin A) into the culture supernatant which cross-reacted with antiserum against Escherichia coli HlyA whereas there was no similar protein detectable with this cross-reactive property from the supernatant of the F. philomiragia strain.
24.	Lehtio, J., et al. (author) Directed immobilization of recombinant staphylococci on cotton fibers by functional display of a fungal cellulose-binding domain 2001 In: FEMS Microbiology Letters. - 0378-1097 .- 1574-6968. ; 195:2, s. 197-204 Journal article (peer-reviewed)abstract The immobilization of recombinant staphylococci onto cellulose fibers through surface display of a fungal cellulose-binding domain (CBD) was investigated. Chimeric proteins containing the CBD from Trichoderma reesei cellulase Cel6A were found to be correctly targeted to the cell wall of Staphylococcus carnosus cells. since full-length proteins could be extracted and affinity-purified. Furthermore. surface accessibility of the CBD was verified using a monoclonal antibody and functionality in terms of cellulose-binding was demonstrated in two different assays in which recombinant staphylococci were found to efficiently bind to cotton fibers. The implications of this strategy of directed immobilization Tor the generation of whole-cell microbial tools Fur different applications will be discussed.
25.	Leitz, G, et al. (author) Laser-based micromanipulation for separation and identification of individual Frankia vesicles 2003 In: FEMS Microbiology Letters. - 0378-1097 .- 1574-6968. ; 224:1, s. 97-100 Journal article (peer-reviewed)abstract In studies of symbiotic efficiency it is of great importance to identify and separate individual Frankia strains from a nodule. Therefore, a new laser-based micromanipulation technique has been developed in which individual vesicles from root nodules of two Frankia-Alnus symbioses have been successfully cut loose and separated from clusters of vesicles in sterile conditions under light microscopy using a laser scalpel and optical tweezers. Vesicles from the Alnus incana-Frankia AvCIl symbiosis were successfully isolated and grown in culture using this technique. The DNA from both Frankia sources was amplified by polymerase chain reaction (PCR). The work shows that a combination of laser-based manipulation techniques and PCR can be used for the separation and study of individual vesicles. This novel laser-based micromanipulation technique opens up various new possibilities, for instance, to study whether several Frankia strains can grow simultaneously in the same root nodule. (C) 2003 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.
26.	Lorca, G, et al. (author) Lactobacilli express cell surface proteins which mediate binding of immobilized collagen and fibronectin 2002 In: FEMS Microbiology Letters. - 1574-6968. ; 206:1, s. 31-37 Journal article (peer-reviewed)abstract Binding of immobilized collagen-I (Cn-I) and fibronectin (Fn) by Lactobacillus acidophilus CRL 639 depends on cell-surface proteins. Capsule formation during the stationary growth phase has a negative effect on adherence of Cn-I and Fn. However, cells from the exponential growth phase. which produce no capsule, exhibit maximal binding. Binding is sensitive to trypsin, proteinase K, pronase E, and heat. Gelatin and soluble Cn-I partially inhibit binding of Cn-I although various proteins, sugars and amino acids do not affect binding to Fn. These results indicate that protein-protein interactions mediate adhesion to extracellular matrix proteins. SDS-PAGE and Western blot analyses of surface proteins revealed that several proteins including the major 43-kDa protein of the S-layer are expressed. Monoclonal antibodies showed that Fn binds to a 15-kDa protein, while Cn-I binds to proteins of 45 and 58 kDa.
27.	Magnusson, Jesper, et al. (author) Broad and complex antifungal activity among environmental isolates of lactic acid bacteria 2003 In: FEMS Microbiology Letters. - : Elsevier. - 0378-1097 .- 1574-6968. ; 219:1, s. 129-135 Journal article (peer-reviewed)abstract More than 1200 isolates of lactic acid bacteria isolated from different environments were screened for antifungal activity in a dual-culture agar plate assay. Approximately 10% of the isolates showed inhibitory activity and 4% showed strong activity against the indicator mould Aspergillus fumigatus. The antifungal spectra for 37 isolates with strong activity and five isolates with low or no activity were determined. Several of the strains showed strong inhibitory activity against the moulds A. fumigatus, Aspergillus nidulans, Penicillium commune and Fusarium sporotrichioides, and also against the yeast Rhodotorula mucilaginosa. Penicillium roqueforti and the yeasts Pichia anomala and Kluyveromyces marxianus were not inhibited. Several isolates showed reduced antifungal activity after storage and handling. The majority of the fungal inhibitory isolates were identified by 16S rDNA sequencing as Lactobacillus coryniformis. Lactobacillus plantarum and Pediococcus pentosaceus were also frequently identified among the active isolates. The degree of fungal inhibition was not only related to production of lactic or acetic acid. In addition, antifungal cyclic dipeptides were identified after HPLC separation and several other active fractions were found suggesting a highly complex nature of the antifungal activity.
28.	Mahmood, Shahid (author) Colonisation of spruce roots by two interacting ectomycorrhizal fungi in wood ash amended substrates 2003 In: FEMS Microbiology Letters. - 1574-6968. ; 221:1, s. 81-87 Journal article (peer-reviewed)abstract Interactions between two ectomycorrhizal fungal species, Piloderma croceum Erikss. and Hjortst. and Piloderma sp. 1 (found to colonise spruce roots and wood ash granules in the field), were investigated in wood ash amended substrates. The comparative ability of these fungi to colonise roots of non-mycorrhizal spruce (Picea abies (L.) Karst.) seedlings was studied in relation to factorial combinations of wood ash and N fertilisation. Non-mycorrhizal spruce seedlings (bait seedlings) were planted together with spruce seedlings colonised by P. croceum or Piloderma sp. 1. The growth substrate was a sand-peat mixture with wood ash or no ash and supplied with two levels of N, so that four substrate combinations were obtained. Piloderma sp. 1 mycelia colonised around 60% of the fine roots of bait seedlings in ash treatments regardless of N level and around 20-26% in treatments without ash. P. croceum only colonised 8% of the root tips in the presence of ash but 56% of the root tips in the low-N treatment without ash. However, in the high-N treatment without ash the colonisation level was reduced to around 30%. Total numbers of root tips per seedling did not vary significantly between the treatments. Possible reasons for the competitive advantage of Piloderma sp. 1 in wood ash fertilised substrate are discussed. (C) 2003 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.
29.	Monstein, Hans-Jurg, 1946-, et al. (author) Rapid molecular identification and subtyping of Helicobacter pylori by pyrosequencing of the 16S rDNA variable V1 and V3 regions 2001 In: FEMS Microbiology Letters. - 0378-1097 .- 1574-6968. ; 199:1, s. 103-107 Journal article (peer-reviewed)abstract We describe here the use of real-time DNA sequence analysis of Helicobacter pylori 16S rRNA gene fragments by pyrosequencingÖ for rapid molecular identification and subtyping of clinical isolates based on DNA sequence heterogeneity within the variable V1 and V3 regions. Six individual 16S rDNA V1 alleles (position 75-100) were identified in 23 clinical isolates obtained from gastric biopsy specimens. Eleven of these revealed sequence identities with H. pylori 26695 and one was identical with the rrn genes in strain J99. The other V1 alleles showing single or double nucleotide mutations or single nucleotide insertions could be divided into four groups with 5, 4, 1, and 1 isolates each. Two out of 25 isolates demonstrated single C to T transitions in the V3 region (position 990-1020). The present findings show that subtle DNA sequence variation occurs sufficiently often in the 16S rDNA variable V1 and V3 regions of H. pylori to provide a consistent system for subtyping.
30.	Moran, AP, et al. (author) Role of Helicobacter pylori rfaJ genes (HP0159 and HP1416) in lipopolysaccharide synthesis 2004 In: FEMS microbiology letters. - : Oxford University Press (OUP). - 0378-1097 .- 1574-6968. ; 241:1, s. 57-65 Journal article (peer-reviewed)
31.	Nahalkova, Jarmila, et al. (author) Red fluorescent protein (DsRed2) as a novel reporter in Fusarium oxysporum f. sp. Lycopersici 2003 In: FEMS Microbiology Letters. - 0378-1097 .- 1574-6968. ; 225:2, s. 305-309 Journal article (peer-reviewed)abstract pAn-DsRed2 vector was constructed for constitutive cytoplasmic expression of the red fluorescent protein (DsRed2) under control of the glyceraldehyde-3-phosphate dehydrogenase gene promoter from Aspergillus nidulans. DsRed2-transformation of two Fusarium oxysporum f. sp. lycopersici strains pathogenic against tomato host resulted in bright red cytoplamic fluorescence of the fungus. The transformants were screened based on the hygromycin B resistance, brightness, stability and rate of appearance of the DsRed2 fluorescence. The transormed fungi were growing normally and their pathogenicity did not change after transformation procedure. The function of novel DsRed2 marker was verified by fluorescence microscopy of the infected tomato seedlings. The results indicate that DsRed2 can be used as a efficient novel reporter gene for monitoring of the F. oxysporum within the host tissues.
32.	Neilands, Jessica, et al. (author) Effect of acid shock on protein expression by biofilm cells of Streptococcus mutans 2003 In: FEMS Microbiology Letters. - : Blackwell, Oxford. - 0378-1097 .- 1574-6968. ; 227:2, s. 287-293 Journal article (peer-reviewed)abstract Streptococcus mutans is a component of the dental plaque biofilm and a major causal agent of dental caries. Log-phase cells of the organism are known to induce an acid tolerance response (ATR) at sub-lethal pH values ( approximately 5.5) that enhances survival at lower pH values such as those encountered in caries lesions. In this study, we have employed a rod biofilm chemostat system to demonstrate that, while planktonic cells induced a strong ATR at pH 5.5, biofilm cells were inherently more acid resistant than such cells in spite of a negli-gible induction of an ATR. Since these results suggested that surface growth itself triggered an ATR in biofilm cells, we were interested in comparing the effects of a pH change from 7.5 to 5.5 on protein syn-thesis by the two cell types. For this, cells were pulse labeled with [(14)C]-amino acids following the pH change to pH 5.5, the proteins extracted and separated by two-dimensional (2D) electrophoresis fol-lowed by autoradiography and computer-assisted image analysis. A comparison between the cells incubated at pH 5.5 and the control biofilm cells revealed 23 novel proteins that were absent in the control cells, and 126 proteins with an altered relative rate of synthesis. While the number of changes in protein expression in the biofilm cells was within the same range as for planktonic cells, the magnitude of their change was significantly less in biofilm cells, supporting the observa-tion that acidification of biofilm cells induced a negligible ATR. Mass spectrometry and computer-assisted protein sequence analysis revealed that ATR induction of the planktonic cells resulted in the downregula-tion of glycolytic enzymes presumably to limit cellular damage by the acidification of the external environment. On the other hand, the gly-colytic enzymes in control biofilm cells were significantly less down-regulated and key enzymes, such as lactate dehydrogenase were upregulated during pH 5.5 incubation, suggesting that the enhanced acid resistance of biofilm cells is associated with the maintenance of pH homeostasis by H+ extrusion via membrane ATPase and increased lactate efflux.
33.	Nilsson, M, et al. (author) A von Willebrand factor-binding protein from Staphylococcus lugdunensis 2004 In: FEMS Microbiology Letters. - 1574-6968. ; 234:1, s. 155-161 Journal article (peer-reviewed)abstract In the present study, a phage display library covering the genome of Staphylococcus lugdunensis, was affinity-selected against von Willebrand factor (vWf). This led to the identification of a gene, vwbl, encoding a Putative cell surface protein of 2060 amino acids, denoted vWbl. The deduced protein has an overall organisation typical of staphylococcal cell Surface proteins, with an N-terminal signal peptide, and a C-terminal cell wall sorting signal. The vWf-binding part is located in repetitive domains and antibodies against vWbl or vWf can inhibit the binding. Southern blot analysis showed that vwbl was present in the 12 S. lugdunensis strains tested. (C) 2004 Federation of European Microbiological Societies.
34.	Nordberg Karlsson, Eva, et al. (author) The modular xylanase Xyn10A from Rhodothermus marinus is cell-attached, and its C-terminal domain has several putative homologues among cell-attached proteins within the phylum Bacteroidetes 2004 In: FEMS Microbiology Letters. - : Oxford University Press (OUP). - 1574-6968 .- 0378-1097. ; 241:2, s. 233-242 Journal article (peer-reviewed)abstract Until recently, the function of the fifth domain of the thermostable modular xylanase Xyn10A from Rhodothermus marinus was unresolved. A putative homologue to this domain was however identified in a mannanase (Man26A) from the same microorganism which raised questions regarding a common function. An extensive search of all accessible data-bases as well as the partially sequenced genomes of R. marinus and Cytophaga hutchinsonii showed that homologues of this domain were encoded by multiple genes in microorganisms in the phylum Bacteroidetes. Moreover, the domain occurred invariably at the C-termini of proteins that were predominantly extra-cellular/cell attached. A primary structure motif of three conserved regions including structurally important glycines and a proline was also identified suggesting a conserved 3D fold. This bioinformatic evidence suggested a possible role of this domain in mediating cell attachment. To confirm this theory, R. marinus was grown, and activity assays showed that the major part of the xylanase activity was connected to whole cells. Moreover, immunocytochemical detection using a Xyn10A-specific antibody proved presence of Xyn10A on the R. marinus cell surface. In the light of this, a revision of experimental data present on both Xyn10A and Man26A was performed, and the results all indicate a cell-anchoring role of the domain, suggesting that this domain represents a novel type of module that mediates cell attachment in proteins originating from members of the phylum Bacteroidetes.
35.	Pallen, Mark J, et al. (author) Tetratricopeptide-like repeats in type-III-secretion chaperones and regulators 2003 In: FEMS Microbiology Letters. - 0378-1097 .- 1574-6968. ; 223:1, s. 53-60 Journal article (peer-reviewed)abstract Efficient type-III secretion depends on cytosolic molecular chaperones, which bind specifically to the translocators and effectors. In the past there has been a tendency to shoe-horn all type-III-secretion chaperones into a single structural and functional class. However, we have shown that the LcrH/SycD-like chaperones consist of three central tetratricopeptide-like repeats that are predicted to fold into an all-alpha-helical array that is quite distinct from the known structure of the SycE class of chaperones. Furthermore, we predict that this array creates a peptide-binding groove that is utterly different from the helix-binding groove in SycE. We present a homology model of LcrH/SycD that is consistent with existing mutagenesis data. We also report the existence of tetratricopeptide-like repeats in regulators of type-III secretion, such as HilA from Salmonella enterica and HrpB from Ralstonia solanacearum. The discovery of tetratricopeptide-like repeats in type-III-secretion regulators and chaperones provides a new conceptual framework for structural and mutagenesis studies and signals a potential unification of prokaryotic and eukaryotic chaperone biology.
36.	Stoll, Dominik, et al. (author) Mannanase Man26A from Cellulomonas fimi has a mannan-binding module 2000 In: FEMS Microbiology Letters. - 1574-6968. ; 183:2, s. 265-269 Journal article (peer-reviewed)abstract A modular mannanase (Man26A) from the bacterium Cellulomonas fimi contains a mannan-binding module (Man26Abm) that binds to soluble but not to insoluble mannans. Man26Abm does not bind to cellulose, chitin or xylan. The Kd for binding of Man26Abm to locust bean gum (LBG) is ~0.2 μM. Man26A is the first mannanase reported to contain a mannan-binding module.
37.	Sundin, Charlotta, et al. (author) ADP-ribosylation by Exoenzyme T of Pseudomonas aeruginosa induces an irreversible effect on the host cell cytoskeleton in vivo 2004 In: FEMS Microbiology Letters. - : Elsevier. - 0378-1097 .- 1574-6968. ; 234:1, s. 87-91 Journal article (peer-reviewed)abstract Pseudomonas aeruginosa utilises a type III secretion system (TTSS) to introduce exoenzyme S and exoenzyme T into host cells to subvert host cell signalling and thereby promote infection. In this study, we have employed the heterologous TTSS of Yersinia to deliver different mutants of ExoT into HeLa cells. Wild-type ExoT and ExoT variants expressing either GAP (GTPase activating protein) or ADP-ribosyltransferase activity mediated changes in cell morphology, which correlated to disruption of the actin microfilaments of the infected cells. ExoT expressing ADP-ribosylating activity gave an irreversible effect on HeLa cell morphology, while ExoT expressing only GAP activity displayed a reversible effect where the cells regained normal cell morphology after killing of the infecting bacteria. This shows that ExoT can modify and inactivate host cell proteins involved in maintaining the actin cytoskeleton in vivo by two independent mechanisms.
38.	Wernérus, Henrik, et al. (author) Vector engineering to improve a staphylococcal surface display system 2002 In: FEMS Microbiology Letters. - 0378-1097 .- 1574-6968. ; 212:1, s. 47-54 Journal article (peer-reviewed)abstract A previously developed expression system for surface display of heterologous proteins on the surface of Staphylococcus carnosus employs the secretion signals from a Staphylococcus hyicus lipase and the cell wall anchoring part of Staphylococcus aureus protein A (SpA) to achieve surface display of expressed recombinant proteins. The system has been successfully used in various applications but the vector has not been considered genetically stable enough to allow protein library display applications, which would be of obvious interest. A new set of vectors, differing in size and devoid of a phage f1 origin of replication, were constructed and evaluated in terms of bacterial growth characteristics and vector stability. Furthermore, surface expression of a model surface protein was monitored by an enzymatic whole-cell assay and flow cytometry. The engineered expression vectors demonstrated dramatically improved stability and growth properties and two of the novel vectors demonstrated retained high surface density of the displayed model protein. The flow cytometry was found to be a powerful toot for observing the surface density of displayed heterologous proteins, and would thus be a rational strategy for monitoring the optimisation of any surface display system. The implications of these improved display vectors for future protein library applications are discussed.
39.	Wouters, Johanna, et al. (author) Cloning and expression of a putative cyclodextrin glucosyltransferase from the symbiotically competent cyanobacterium Nostoc sp PCC 9229 2003 In: FEMS Microbiology Letters. - 0378-1097 .- 1574-6968. ; 219:2, s. 181-185 Journal article (peer-reviewed)abstract A polymerase chain reaction-based method was used to isolate a Nostoc sp. PCC 9229 cDNA from infected glands of Gunnera chilensis. The complete gene sequence was isolated from a genomic Nostoc sp. PCC 9229 library. Sequence analysis showed 84% amino acid similarity to a putative cyclodextrin glycosyltransferase from Nostoc sp. PCC 7120 and the gene was therefore termed cgt. Southern blot revealed that the cgt gene was present in symbiotically competent cyanobacteria. The cgt gene was expressed in free-living nitrogen-fixing cultures in light or in darkness when supplemented with fructose. This is the first expression analysis of a cgt gene from a cyanobacterium. (C) 2003 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.

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