| 1. |
- Gyllenram, Rutger, et al.
(författare)
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Blast furnace control after the year 2000
- 1996
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Ingår i: Steelmaking Conference Proceedings. - : Iron & Steel Soc of AIME, Warrendale, PA, United States. ; , s. 685-692
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Konferensbidrag (refereegranskat)abstract
- Rapid technical development together with developments in work organization makes it important to investigate possible ways to achieve a cost efficient process control of different metallurgical processes. This paper describes a research project, and proposes a human oriented Information Technology Strategy, ITS, for control of the Blast Furnace process. The method used is that of deductive reasoning from a description of the prevailing technological level and experiences from various development activities. The paper is based on experiences from the No. 2 Blast Furnace at Lulea Works but the conclusions do not at this stage necessarily reflect the opinion of the management and personnel or reflect their intentions for system development at SSAB.
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| 2. |
- Nilson, Bo, et al.
(författare)
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Structure and stability of protein H and the M1 protein from Streptococcus pyogenes. Implications for other surface proteins of gram-positive bacteria
- 1995
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Ingår i: Biochemistry. - : American Chemical Society (ACS). - 0006-2960 .- 1520-4995. ; 34:41, s. 13688-13698
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Tidskriftsartikel (refereegranskat)abstract
- M proteins and other members of the M protein family, expressed on the surface of Streptococcus pyogenes, bind host proteins such as immunoglobulins, albumin, and fibrinogen. Protein H and the M1 protein are expressed by adjacent genes and both belong to the M protein family. In this work, the structure and stability of these two proteins have been investigated. As judged from sequence analysis and circular dichroism spectroscopy, the proteins are almost entirely in an alpha-helix conformation. The amino acids are arranged in a seven-residue (heptad) repeat pattern along the greater part of the proteins. These observations support the previously accepted model of M proteins as coiled-coil dimers. However, it was also found that the structures of both proteins were thermally unstable; i.e., the content of helix conformation was greatly reduced at 37 degrees C as compared to 25 degrees C or below. Together with previous findings that these proteins appear as monomers at 37 degrees C and dimers at low temperatures, the results suggest that the coiled-coil dimers are unfolded at 37 degrees C. The heptad patterns of protein H and the M1 protein showed a nonoptimal distribution of residues expected for a coiled-coil conformation. This is a possible explanation for the low thermal stability of the proteins. It was also demonstrated that the proteins were stabilized in the presence of the ligands IgG and/or albumin. Protein H and M1 protein show a high degree of sequence similarity in their C-terminal regions, and a fragment from this region displayed a high content of helix conformation, whereas fragments from the nonsimilar N-terminal parts did not adopt any stable folded structure. Thus, the C-terminal parts, which are conserved within the M protein family, may constitute a framework for the formation of the parallel helical coiled-coil structure, and we propose that the less stable N-terminal part may also participate in antiparallel interaction with M proteins on adjacent bacteria. The results suggest that temperature fluctuations in the environment could change the properties of bacterial surface proteins, thereby affecting the molecular interactions between the bacterium and its host.
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| 3. |
- Rosén, Stefan, et al.
(författare)
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Molecular characterization of a saline-soluble lectin from a parasitic fungus : Extensive sequence similarities between fungal lectins
- 1996
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Ingår i: European Journal of Biochemistry. - : Wiley. - 0014-2956 .- 1432-1033. ; 238:3, s. 822-829
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Tidskriftsartikel (refereegranskat)abstract
- It has been proposed that the interactions between several parasite and pathogenic fungi and their hosts are mediated by soluble lectins present in the fungus. We have cloned and analyzed a gene encoding such a lectin (AOL) from the nematophagous fungus Arthrobotrys oligospora (deuteromycete). The deduced primary structure of the AOL gene displayed an extensive similarity (identity 46.3%) to that of a gene encoding a lectin (ABL) recently isolated from the mushroom Agaricus bisporus (basidiomycete), but not to any other fungal, microbial, plant, or animal lectins. The similarities between AOL and ABL were further demonstrated by the observation that an antibody specific for AOL cross-reacted with ABL. Together with data showing that AOL has a binding specificity that is similar to that of ABL [Rosen, S., Bergstrom, J., Karlsson, K.-A., and Tunlid, A. (1996) Eur. J. Biochem. 238, 830-837], these results indicate that AOL and ABL are members of a novel family of saline- soluble lectins present in fungi. Southern blots indicated that there is only one AOL gene in the genome encoding a subunit (monomer) of the lectin. The primary structure of AOL did not show the presence of a typical N-terminal signal sequence. Comparison of the deduced primary structure with the molecular mass of AOL as determined by electrospray mass spectrometry (16153 Da), indicated that AOL has an acetylated N-terminal but no other post- translational modifications, and that a minor isoform is formed by deamidation. Circular dichroism (CD) spectroscopy suggested that the secondary structure of AOl contains 34% β-sheets, 21% α-helix, and 45% turns and coils.
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