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Antonie van Leeuwenhoek

, Volume 75, Issue 4, pp 299–307 | Cite as

The role of peptidoglycan structure and structural dynamics during endospore dormancy and germination

  • Abdelmadjid Atrih
  • Simon J. FosterEmail author
Article

Abstract

Dormant, bacterial endospores are the most resistant living structures known. The spore cell wall (cortex) maintains dormancy, core dehydration, and heat resistance. The cortex peptidoglycan has a unique, spore specific structure that enables it to fulfill its role. The cross-linking index of spore cortex peptidoglycan is very low, occurring at only 2.9% of the muramic acid residues compared to 33% in vegetative cells. The level of cross-linking of the cortex may be important in maintaining spore dormancy and heat resistance. Approximately 50% of the muramic acid residues in spore cortex are substituted with muramic δ-lactam. This modification is spore specific and is the major characteristic feature of the cortex. The muramic δ-lactam has no apparent role in establishing core dehydration, maintaining dormancy or heat resistance. However, the muramic δ-lactam residues are necessary for spore cortex hydrolysis during germination. They constitute part of the substrate recognition profile of the germination specific lytic enzymes (GSLEs) which are responsible for cortex hydrolysis.

Germination results in loss of dormant spore properties and hydrolysis of the cortex is essential for later germination events and outgrowth. Application of muropeptide analysis to determine peptidoglycan structural dynamics during germination has revealed an unexpected degree of complexity in peptidoglycan hydrolysis. At least three hydrolytic activities, an N-acetyl glucosaminidase, a lytic transglycosylase and a possible amidase, are involved. A non-hydrolytic acitivity, likely to be an epimerase of muramic acid also occurs early during germination.

The lytic transglycosylase generates anhydro-muropeptides which are released during germination and may be recycled during outgrowth to form part of the new vegetative cell wall.

germination peptidoglycan hydrolysis peptidoglycan structure spores 

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References

  1. Alderton G & Snell NS (1963) Base exchange and heat resistance in bacterial spores. Biochem. Biophy. Research Commun. 10: 139–143Google Scholar
  2. Atrih A, Bacher G, Allmaier G & Foster SJ (1999) Structural analysis of Bacillus megaterium endospore peptidoglycan and its structural dynamics during germination. Microbiology 145: 1033–1041Google Scholar
  3. Atrih A, Zöllner P, Allmaier G & Foster SJ (1996) Structural analysis of Bacillus subtilis 168 endospore peptidoglycan and its role during differentiation. J. Bacteriol. 178: 6173–6183Google Scholar
  4. Atrih A, Zöllner P, Allmaier G, Williamson M & Foster SJ (1998) Peptidoglycan structural dynamics during germination of Bacillus subtilis 168 endospores. J. Bacteriol. 180: 4603–4612Google Scholar
  5. Brown KL (1994) Spore resistance and ultra heat treatment processes. J. Appl. Bacteriol. 76: 67S-80SGoogle Scholar
  6. Cassier M & Ryter A (1971) Sur un mutant de Clostridium perfringens donnant des spores sans tuniques a germination lysosyme-dependante. Ann. Inst. Pasteur 121: 717–732Google Scholar
  7. Chen Y, Miyata S, Makino S & Moriyama R (1997) Molecular characterization of a germination-specific muramidase from Clostridium perfringens S40 spores and nucleotide sequence of the corresponding gene. J. Bacteriol. 179: 3181–3187Google Scholar
  8. Ellar DJ (1978) Spore specific structures and their function. Symp. Soc. Gen. Microbiol. 28: 295–334Google Scholar
  9. Errington J (1993) Bacillus subtilis sporulation: regulation of gene expression and control of morphogenesis. Microbiol. Rev. 57: 1–33Google Scholar
  10. Foster SJ & Johnstone K (1987) Purification and properties of a germination-specific cortex lytic enzyme from spores of Bacillus megaterium KM. Biochem. J. 242: 573–579Google Scholar
  11. Foster SJ & Johnstone K (1990) Pulling the trigger: the mechanism of bacterial spore germination. Mol. Microbiol. 4: 137–141Google Scholar
  12. Foster SJ & Johnstone K (1988) Germination-specific cortex-lytic enzyme is activated during triggering of Bacillus megaterium KM spore germination. Mol. Microbiol. 2: 727–733Google Scholar
  13. Fukuoka H, Miyata S, Kudoh S, Hatori S, Makino S & Moriyama R (1998) Diversity and expression and activation of germination-specific amidase between Clostridium perfringens and Bacilli (p 89). Abstracts of the International Conference on Bacilli. Osaka, JapanGoogle Scholar
  14. Gerhardt P & Marquis RE (1989) Spore thermoresistance mechanisms. In: Smith I, Slepecky R & Setlow P (Eds) Regulation of procaryotic development (pp 43–63). American Society for Microbiology, Washington, DCGoogle Scholar
  15. Cleveland EF & Gilvarg C (1975) Selective degradation of peptidoglycan from Bacillus megaterium during germination. In: Gerhardt P, Costilow RN & Sadoff HL (Eds) Spores VI (pp 458–464). American Society for Microbiology, Washington, DCGoogle Scholar
  16. Gould GW (1970) Germination and the problem of dormancy. J. Appl. Bacteriol. 33: 34–49Google Scholar
  17. Gould GW (1984) Mechanisms of resistance and dormancy. In: Hurst A & Gould GW (Eds) The bacterial spore, Vol. 2 (pp 173–209). Academic Press, LondonGoogle Scholar
  18. Hsieh LK & Vary JC (1975) Germination and peptidoglycan solubilisation in Bacillus megaterium spores. J. Bacteriol. 123: 463–470Google Scholar
  19. Imae Y & Strominger JL (1976) Relationship between cortex content and properties of Bacillus sphaericus spores. J. Bacteriol. 126: 907–913Google Scholar
  20. Ishikawa S, Yamane K & Sekiguchi J (1998) Regulation and characterization of a newly deduced cell wall hydrolase gene (cwlJ) which affects germination of Bacillus subtilis spores. J. Bacteriol. 180: 1375–1380Google Scholar
  21. Jacobs C, Joris B, Jamin M, Klarsov K, van Heijenoort J, Park JT, Normark S & Frere JM (1995) AmpD, essential for both β-lactamase regulation and cell wall recycling, is a novel cytosolic N-acetylmuramyl-L-alanine amidase. Mol. Microbiol. 15: 553–559.Google Scholar
  22. Jacobs C, Frere LJ, Bartowsky E & Normark S (1997) Cytosolic intermediates for cell wall biosynthesis and degradation control inducible β-lactam resistance in Gram-negative bacteria. Cell 88: 823–832Google Scholar
  23. Jacobs C, Huang LJ, Bartowsky E, Normark S & Park JT (1994) Bacterial cell wall recycling provide cytosolic muropeptides as effectors for β-lactamase induction. EMBO. J. 13: 4684–4694Google Scholar
  24. Johnstone K & DJ Ellar (1982) The role of cortex hydrolysis in the triggering of germination of Bacillus megaterium KM endospores. Biochem. Biophys. Acta. 794: 185–191Google Scholar
  25. Johnstone K (1994) The trigger mechanism of spore germination: current concepts. J. Appl. Bacteriol. 76: 17S-24SGoogle Scholar
  26. Kitano K, Tuomanen E & Tomasz A (1986) Transglycosylase and endopeptidase participate in the degradation of murein during autolysis of Escherichia coli. J. Bacteriol. 167: 759–765Google Scholar
  27. Kunst et al. (1997) The complete genome sequence of the Grampositive bacterium Bacillus subtilis. Nature 390: 249–256Google Scholar
  28. Makino S, Ito N, Inoue T, Miyata S & Moriyama R (1994) A spore-lytic enzyme released from Bacillus cereus during germination. Microbiology 140: 1403–1410Google Scholar
  29. Miyata S, Moriyama R, Miyahara N & Makino S (1995a) A gene (sleC) encoding a spore cortex-lytic enzyme from Clostridium perfringens S40 spore; cloning sequence analysis and molecular characterization. Microbiology 141: 2643–2650Google Scholar
  30. Miyata S, Moriyama R, Sugimoto K & Makino S (1995b) Purification and partial characterization of a spore cortex-lytic enzyme of Clostridium perfringens S40 spores. Biosci. Biotechnol. Biochem. 59: 514–515Google Scholar
  31. Moriyama R, Kudoh S, Miyata S, Nonobe S, Hattori A & Makino S (1996a) A germination-specific spore cortex-lytic enzyme from Bacillus cereus spores: cloning and sequencing of the gene and molecular characterization of the enzyme. J. Bacteriol. 178: 5330–5332Google Scholar
  32. Moriyama R, Hattori A, Miyata S, Kudoh, S & Makino S (1996b) A gene (sleB) encoding a spore-lytic enzyme from Bacillus subtilis and response of the enzyme to L-alanine-mediated germination. J. Bacteriol. 178: 6059–6063Google Scholar
  33. Murrell WG & Warth AD (1965) Composition and heat resistance of bacterial spores. In: Campell LL & Halvorson HO (Eds) Spores III (pp 1–24). American Society for MicrobiologyGoogle Scholar
  34. Nakatani Y, Tanida I, Koshikawa T, Imagawa M, Nishihara T & Kondo M (1985) Collapse of cortex expansion during germination of Bacillus megaterium spores. Microbiol. Immunol. 29: 689–699Google Scholar
  35. Popham DL, Helm J, Costello CE & Setlow P (1996b) Analysis of the peptidoglycan structure of Bacillus subtilis endospores. J. Bacteriol. 178: 6451–6458Google Scholar
  36. Popham DL, Helm J, Costello CE & Setlow P (1996a) Muramic lactam in peptidoglycan of Bacillus subtilis spores is required for spore outgrowth but not spore dehydration or heat resistance. Proc. Natl. Acad. Sci. USA 93: 15405–15410Google Scholar
  37. Popham DL, Illades-Aguiar B & Setlow P (1995) The Bacillus subtilis dacB gene, encoding penicillin-binding protein 5*, is part of a three-gene operon required for proper spore cortex synthesis and spore core dehydration. J. Bacteriol. 177: 4721–4729Google Scholar
  38. Sekiguchi JK, Akeo H, Yamamoto FK, Khasanov JC, Alonso & Kuroda A (1995) Nucleotide sequence and regulation of a new putative cell wall hydrolase gene, cwlD, Which affects germination in Bacillus subtilis. J. Bacteriol. 177: 5582–5589Google Scholar
  39. Setlow P (1994) Mechanism which contribute to the long-term survival of spores of Bacillus species. J. Appl. Bacteriol. 76: 49S-60SGoogle Scholar
  40. Tani K, Watanabe T, Matsuda H, Nasu M & Kondo M (1996) Cloning and sequencing of the spore germination gene of Bacillus megaterium ATCC 12872: similarities to the NaH-Antiporter gene of Enterococcus hirae. 40: 99–105Google Scholar
  41. Tipper DJ & Gauthier JJ (1972) Structure of the bacterial endospore. In: Halvorson HO, Hanson R & Campbell LL (Eds) Spores V (pp 3–12). American Society for Microbiology, Washington, DCGoogle Scholar
  42. Warth AD & Strominger JL (1969) Structure of bacterial spores: occurrence of the lactam of muramic acid. Proc. Natl. Acad. Sci. USA 64: 528–535Google Scholar
  43. Warth AD & Strominger JL (1971) Structure of the peptidoglycan from vegetative cell wall of Bacillus subtilis. Biochemistry 10: 4349–4358Google Scholar
  44. Warth AD & Strominger JL (1972) Structure of the peptidoglycan from spores of Bacillus subtilis. Biochemistry 11: 1389–1396Google Scholar
  45. Warth AD (1978) Molecular structure of the bacterial spore. Adv. Microb. Physiol. 17: 1–47Google Scholar
  46. Wax R & Freeze E (1968) Initiation of the germination of Bacillus subtilis spores by a combination of compounds in place of L-alanine. J. Bacteriol. 95: 433–438Google Scholar

Copyright information

© Kluwer Academic Publishers 1999

Authors and Affiliations

  1. 1.Department of Molecular Biology and BiotechnologyUniversity of SheffieldSheffieldUnited Kingdom

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