Abstract
The structure of the regular surface layer of Aquaspirillum serpens MW5 has been investigated by electon microscopy supplemented by computer image processing and least-squares analysis. The layer has a ribbed appearance, both on the bacterium and in isolated, negatively stained fragments. However, detailed analysis indicated that the layer was composed of two hexagonal sheets having p6mm symmetry and a = 16 nm. One sheet was staggered by one half repeat along a (1,0) line of the p6nm lattice relative to the second so that, in projection, the pattern of the composite layer was a translational moiré, characterized by a series of ribs spaced 16 nm apart. The ribbed layer had cmm symmetry with a = 32 nm and b = 18.5 nm. Analysis of this pattern indicated that the two p6nm hexagonal sheets were unevenly stained, and this was confirmed by using least-squares methods to simulate the observed pattern by combining two hexagonal patterns. The general structure of the layer was consistent with a role as a selective and protective barrier on the cell surface.
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Selected References
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- Aebi U., Smith P. R., Dubochet J., Henry C., Kellenberger E. A study of the structure of the T-layer of Bacillus brevis. J Supramol Struct. 1973;1(6):498–522. doi: 10.1002/jss.400010606. [DOI] [PubMed] [Google Scholar]
- Amos L. A. Image analysis of macromolecular structures. J Microsc. 1974 Mar;100(2):143–152. doi: 10.1111/j.1365-2818.1974.tb03924.x. [DOI] [PubMed] [Google Scholar]
- Beveridge T. J., Murray R. G. Surface arrays on the cell wall of Spirillum metamorphum. J Bacteriol. 1975 Dec;124(3):1529–1544. doi: 10.1128/jb.124.3.1529-1544.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Beveridge T. J. Ultrastructure, chemistry, and function of the bacterial wall. Int Rev Cytol. 1981;72:229–317. doi: 10.1016/s0074-7696(08)61198-5. [DOI] [PubMed] [Google Scholar]
- Buckmire F. L., Murray R. G. Studies on the cell wall of Spirillum serpens. 1. Isolation and partial purification of the outermost cell wall layer. Can J Microbiol. 1970 Oct;16(10):1011–1022. doi: 10.1139/m70-171. [DOI] [PubMed] [Google Scholar]
- Buckmire F. L., Murray R. G. Studies on the cell wall of Spirillum serpens. II. Chemical characterization of the outer structured layer. Can J Microbiol. 1973 Jan;19(1):59–66. doi: 10.1139/m73-009. [DOI] [PubMed] [Google Scholar]
- Chester I. R., Murray R. G. Protein-lipid-lipopolysaccharide association in the superficial layer of Spirillum serpens cell walls. J Bacteriol. 1978 Feb;133(2):932–941. doi: 10.1128/jb.133.2.932-941.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Crowther R. A., Klug A. Structural analysis of macromolecular assemblies by image reconstruction from electron micrographs. Annu Rev Biochem. 1975;44:161–182. doi: 10.1146/annurev.bi.44.070175.001113. [DOI] [PubMed] [Google Scholar]
- Finch J. T., Klug A., Nermut M. V. The structure of the macromolecular units on the cell walls of Bacillus polymyxa. J Cell Sci. 1967 Dec;2(4):587–590. doi: 10.1242/jcs.2.4.587. [DOI] [PubMed] [Google Scholar]
- Glaeser R. M., Chiu W., Grano D. Structure of the surface layer protein of the outer membrane of Spirillum serpens. J Ultrastruct Res. 1979 Mar;66(3):235–242. doi: 10.1016/s0022-5320(79)90121-7. [DOI] [PubMed] [Google Scholar]
- Sleytr U. B. Regular arrays of macromolecules on bacterial cell walls: structure, chemistry, assembly, and function. Int Rev Cytol. 1978;53:1–62. doi: 10.1016/s0074-7696(08)62240-8. [DOI] [PubMed] [Google Scholar]
- Stewart M., Beveridge T. J., Murray R. G. Structure of the regular surface layer of Spirillum putridiconchylium. J Mol Biol. 1980 Feb 15;137(1):1–8. doi: 10.1016/0022-2836(80)90153-9. [DOI] [PubMed] [Google Scholar]
- Stewart M., Beveridge T. J. Structure of the regular surface layer of Sporosarcina ureae. J Bacteriol. 1980 Apr;142(1):302–309. doi: 10.1128/jb.142.1.302-309.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stewart M. Structures of alpha-tropomyosin magnesium paracrystals. II. Stimulation of staining patterns from the sequence and some observations on the mechanism of positive staining. J Mol Biol. 1981 Jun 5;148(4):411–425. doi: 10.1016/0022-2836(81)90184-4. [DOI] [PubMed] [Google Scholar]
- Thorne K. J. Regularly arranged protein on the surfaces of Gram-negative bacteria. Biol Rev Camb Philos Soc. 1977 May;52(2):219–234. doi: 10.1111/j.1469-185x.1977.tb01351.x. [DOI] [PubMed] [Google Scholar]