| 1. |
- Nessa, K, et al.
(författare)
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Alveolar macrophage reaction to Candida species
- 1997
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Ingår i: Letters in applied microbiology. - : Oxford University Press (OUP). - 0266-8254 .- 1472-765X. ; 25:3, s. 181-185
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Tidskriftsartikel (refereegranskat)
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| 2. |
- Blomqvist, Johanna, et al.
(författare)
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Fermentation of lignocellulosic hydrolysate by the alternative industrial ethanol yeast Dekkera bruxellensis
- 2011
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Ingår i: Letters in Applied Microbiology. - Malden, USA : Wiley-Blackwell. - 0266-8254 .- 1472-765X. ; 53:1, s. 73-78
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Tidskriftsartikel (refereegranskat)abstract
- Aim: Testing the ability of the alternative ethanol production yeast Dekkera bruxellensis to produce ethanol from lignocellulose hydrolysate and comparing it to Saccharomyces cerevisiae.Methods and Results: Industrial isolates of D. bruxellensis and S. cerevisiae were cultivated in small-scale batch fermentations of enzymatically hydrolysed steam exploded aspen sawdust. Different dilutions of hydrolysate were tested. None of the yeasts grew in undiluted or 1 : 2 diluted hydrolysate [final glucose concentration always adjusted to 40 g l(-1) (0.22 mol l(-1))]. This was most likely due to the presence of inhibitors such as acetate or furfural. In 1 : 5 hydrolysate, S. cerevisiae grew, but not D. bruxellensis, and in 1 : 10 hydrolysate, both yeasts grew. An external vitamin source (e.g. yeast extract) was essential for growth of D. bruxellensis in this lignocellulosic hydrolysate and strongly stimulated S. cerevisiae growth and ethanol production. Ethanol yields of 0 42 +/- 0 01 g ethanol (g glucose)(-1) were observed for both yeasts in 1 : 10 hydrolysate. In small-scale continuous cultures with cell recirculation, with a gradual increase in the hydrolysate concentration, D. bruxellensis was able to grow in 1 : 5 hydrolysate. In bioreactor experiments with cell recirculation, hydrolysate contents were increased up to 1 : 2 hydrolysate, without significant losses in ethanol yields for both yeasts and only slight differences in viable cell counts, indicating an ability of both yeasts to adapt to toxic compounds in the hydrolysate.Conclusions: Dekkera bruxellensis and S. cerevisiae have a similar potential to ferment lignocellulose hydrolysate to ethanol and to adapt to fermentation inhibitors in the hydrolysate.Significance and Impact of the study: This is the first study investigating the potential of D. bruxellensis to ferment lignocellulosic hydrolysate. Its high competitiveness in industrial fermentations makes D. bruxellensis an interesting alternative for ethanol production from those substrates.
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| 3. |
- Enwall, Karin, et al.
(författare)
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Comparison of T-RFLP and DGGE techniques to assess denitrifier community composition in soil
- 2009
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Ingår i: Letters in Applied Microbiology. - 0266-8254 .- 1472-765X. ; 48, s. 145-148
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Tidskriftsartikel (refereegranskat)abstract
- Terminal restriction fragment length polymorphism (T-RFLP) and denaturing gradient gel electrophoresis (DGGE) and subsequent statistical analysis were compared with assess denitrifier community composition in agricultural soil based on the nosZ gene, encoding the nitrous oxide reductase. Analysis of binary or relative abundance-based metric and semi-metric distance matrices provided similar results for DGGE, but not for T-RFLP. Moreover, DGGE had a higher resolution than T-RFLP and binary data was better for discriminating between samples.
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| 4. |
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| 5. |
- Holm, Tina, et al.
(författare)
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Cell-penetrating peptides as antifungals towards Malassezia sympodialis
- 2012
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Ingår i: Letters in Applied Microbiology. - 0266-8254 .- 1472-765X. ; 54:1, s. 39-44
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To determine whether different antimicrobial peptides (AMPs) and cell-penetrating peptides (CPPs) are able to inhibit the growth of the commensal yeast Malassezia sympodialis, which can act as a trigger factor in different skin disorders, such as atopic eczema (AE), seborrhoeic eczema (SE) and dandruff. Methods and results: The antifungal activity of 21 different AMPs and CPPs was investigated by microdilution assay and plate counting to determine the number of colony forming units. Five CPPs and one AMP showed fungicidal activity at submicromolar concentrations. Importantly, no membrane damage on human keratinocytes was detected after peptide treatment. Conclusions: Several CPPs, while being nontoxic to mammalian cells, possess growth inhibitory activity on the very stringent yeast M. sympodialis. Significance and impact of study: Our findings that the CPPs and one AMP that are harmless towards mammalian cells act as antifungal agents against sympodialis opens up the possibility to use these in the treatment for AL, SE and dandruff. To our knowledge, this is the first time peptides have been identilied as antilungal agents against sympodialis. Further studies to ekicidate the mechanism are warranted.
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| 6. |
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| 7. |
- Loncarevic, Semir, et al.
(författare)
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A case of foodborne listeriosis in Sweden
- 1997
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Ingår i: Letters in Applied Microbiology. - : John Wiley & Sons. - 0266-8254 .- 1472-765X. ; 24:1, s. 65-68
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Tidskriftsartikel (refereegranskat)abstract
- A 70-year-old woman fell seriously ill overnight with meningitis and was admitted to hospital. Cerebrospinal fluid culture yielded Listeria monocytogenes. One of the first problems in solving a human case of listeriosis suspected to be foodborne is to find the foods likely to have been transmitting L. monocytogenes. Two enrichment procedures and a direct plating procedure were used for isolation of the bacteria from different food items collected from the patient's refrigerator, local retail store and producer. Samples of vacuum-packed products of sliced pork brawn, sliced cooked medwurst and berliner wurst of the same brand harboured L. monocytogenes. Serotyping and restriction enzyme analysis (REA) with pulsed-field gel electrophoresis (PFGE) were used to characterize and compare 41 isolates, including the human strain. At least three clones were present in the foods investigated, and one of these was identical to the human clone. This clone was present in samples of medwurst from the patient's refrigerator and the local retail store. This is, to our knowledge, the first proven foodborne case of listeriosis reported in Sweden.
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| 8. |
- Loncarevic, Semir, et al.
(författare)
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The clones of Listeria monocytogenes detected in food depend on the method used
- 1996
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Ingår i: Letters in Applied Microbiology. - : Blackwell Science. - 0266-8254 .- 1472-765X. ; 22:5, s. 381-384
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Tidskriftsartikel (refereegranskat)abstract
- Restriction enzyme analysis (REA) with pulsed-field gel electrophoresis (PFGE) has been used to characterize and compare Listeria monocytogenes strains isolated from foods by two methods, an enrichment procedure and a direct plating procedure. In total 151 isolates from nine foods were investigated, In six of the foods (101 strains investigated) only one clone of L, monocytogenes was found irrespective of the method used. In three foods (50 strains investigated) the direct plating procedure yielded more clones than the enrichment procedure. At the most, five clones were detected in the same food. The results presented here indicate that direct plating from the food reveals more L, monocytogenes clones than revealed by an enrichment procedure.
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| 9. |
- Nilsson, Anders, et al.
(författare)
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Detection of Yersinia enterocolitica in food by PCR amplification
- 1998
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Ingår i: Letters in Applied Microbiology. - Oxon, United Kingdom : Blackwell Publishing. - 0266-8254 .- 1472-765X. ; 26, s. 140-144
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Tidskriftsartikel (refereegranskat)abstract
- A polymerase chain reaction (PCR) assay was developed for detection ofpathogenic, virulent strains of Yersinia enterocolitica. By using both virulence loci virFand ail as markers for pathogenicity, detection of species with a virulence factor present waspossible. DNA preparation in the presence of hexadecyl trimethy ammonium bromide(CTAB) was followed by two 44 cycle amplification reactions, one for each of themarkers. As few as 102Y. enterocolitica cells were detected in ground pork in thepresence of 105–106bacteria of other species. The described PCR assay providesa sensitive robust assay for the detection of virulent Y. enterocolitica in food.
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| 10. |
- Nowrouzian, Forough, 1957, et al.
(författare)
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Effect of human milk on type 1 and P-fimbrial mRNA expression in intestinal Escherichia coli strains.
- 2005
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Ingår i: Letters in applied microbiology. - 0266-8254 .- 1472-765X. ; 40:1, s. 74-80
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: Escherichia coli from breastfed infants express more type 1 fimbriae and less P fimbriae than E. coli from bottle-fed infants. In this study we investigated the effect of human milk on production of mRNA for fimA (type 1 fimbriae) and papC (P fimbriae) in E. coli. METHODS AND RESULTS: Production of adhesin gene mRNA was estimated using a reverse transcriptase polymerase chain reaction in E. coli strains under different culture conditions. More type 1 fimbrial mRNA was produced after culture in human milk (P=0.001) or Luria broth (P=0.014) than after culture on agar, whereas P-fimbrial mRNA production was similar under all tested growth conditions. When cultured on agar, E. coli strains carrying both the fim and pap operons produced less type 1 and P-fimbrial mRNA than strains that had only the fim or pap operons, respectively (P=0.03 and 0.056). SIGNIFICANCE AND IMPACT OF THE STUDY: Environmental regulation of adhesin expression may be influenced by cross-talk between fimbrial operons.
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