Mesosome
Mesosomes are folded invaginations in the plasma membrane of bacteria that are produced by the chemical fixation techniques used to prepare samples for electron microscopy. Although several functions were proposed for these structures in the 1960s, they were recognized as artifacts by the late 1970s and are no longer considered to be part of the normal structure of bacterial cells.
Initial observations
These structures are invaginations of the plasma membrane observed in gram-positive bacteria that have been chemically fixed to prepare them for electron microscopy.[2] They were first observed in 1953,[3] and termed mesosomes by JD Robertson in 1959.[4] Initially, it was thought that mesosomes might play a role in several cellular processes, such as cell wall formation during cell division, chromosome replication, or as a site for oxidative phosphorylation.[5][6]
Disproof of hypothesis
These models were called into question during the late 1970s when data accumulated suggesting that mesosomes are artifacts formed through damage to the membrane during the process of chemical fixation, and do not occur in cells that have not been chemically fixed.[2][7][8] By the mid to late 1980s, with advances in cryofixation and freeze substitution methods for electron microscopy, it was generally concluded that mesosomes do not exist in living cells.[9][10][11] However, a few researchers continue to argue that the evidence remains inconclusive, and that mesosomes might not be artifacts in all cases.[12][13]
Recently, similar folds in the membrane have been observed in bacteria that have been exposed to some classes of antibiotics,[14] and antibacterial peptides (defensins).[15] The appearance of these mesosome-like structures may be the result of these chemicals damaging the plasma membrane or cell wall.[16]
The case of the proposal and then disproof of the mesosome hypothesis has been discussed from the viewpoint of the philosophy of science as an example of how a scientific idea can be falsified and the hypothesis then rejected, and a way to explore how the scientific community carries out this testing process.[17][18][3]
See also
References
- ^ Nanninga N (1971). "The mesosome of Bacillus subtilis as affected by chemical and physical fixation". J. Cell Biol. 48 (1): 219–24. PMID 4993484.
- ^ a b Silva MT, Sousa JC, Polónia JJ, Macedo MA, Parente AM (1976). "Bacterial mesosomes. Real structures or artifacts?". Biochim. Biophys. Acta. 443 (1): 92–105. PMID 821538.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ a b Allchin, D. (2000). "The Epistemology of Error" (PDF). Philosophy of Science Association Meetings, Vancouver, November. Retrieved 2008-03-08.
- ^ Robertson, J.D. (1959). "The ultra structure of cell membranes and their derivatives, Biochem". Soc. Syrup: 3.
- ^ Suganuma A (1966). "Studies on the fine structure of Staphylococcus aureus". J Electron Microsc (Tokyo). 15 (4): 257–61. PMID 5984369.
- ^ Pontefract RD, Bergeron G, Thatcher FS (1969). "Mesosomes in Escherichia coli". J. Bacteriol. 97 (1): 367–75. PMID 4884819.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Ebersold HR, Cordier JL, Lüthy P (1981). "Bacterial mesosomes: method dependent artifacts". Arch. Microbiol. 130 (1): 19–22. PMID 6796029.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Higgins ML, Tsien HC, Daneo-Moore L (1976). "Organization of mesosomes in fixed and unfixed cells". J. Bacteriol. 127 (3): 1519–23. PMID 821934.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Ryter A (1988). "Contribution of new cryomethods to a better knowledge of bacterial anatomy". Ann. Inst. Pasteur Microbiol. 139 (1): 33–44. PMID 3289587.
- ^ Nanninga N, Brakenhoff GJ, Meijer M, Woldringh CL (1984). "Bacterial anatomy in retrospect and prospect". Antonie Van Leeuwenhoek. 50 (5–6): 433–60. PMID 6442119.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Dubochet J, McDowall AW, Menge B, Schmid EN, Lickfeld KG (1983). "Electron microscopy of frozen-hydrated bacteria". J. Bacteriol. 155 (1): 381–90. PMID 6408064.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ John F. Stolz (1991) "Structure of Phototrophic Prokaryotes" CRC Press ISBN 0-849-34814-5
- ^ Murata, K. (2008). "Superchannel of Bacteria: Biological Significance and New Horizons". Bioscience, Biotechnology, and Biochemistry: 801080710. Retrieved 2008-03-06.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ Santhana Raj L, Hing HL, Baharudin O; et al. (2007). "Mesosomes are a definite event in antibiotic-treated Staphylococcus aureus ATCC 25923". Trop Biomed. 24 (1): 105–9. PMID 17568383.
{{cite journal}}: Explicit use of et al. in:|author=(help)CS1 maint: multiple names: authors list (link) - ^ Friedrich CL, Moyles D, Beveridge TJ, Hancock RE (2000). "Antibacterial action of structurally diverse cationic peptides on gram-positive bacteria". Antimicrob. Agents Chemother. 44 (8): 2086–92. PMID 10898680.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Balkwill DL, Stevens SE (1980). "Effects of penicillin G on mesosome-like structures in Agmenellum quadruplicatum". Antimicrob. Agents Chemother. 17 (3): 506–9. PMID 6775592.
- ^ Culp, S. (1994). "Defending Robustness: The Bacterial Mesosome as a Test Case". PSA: Proceedings of the Biennial Meeting of the Philosophy of Science Association. 1994: 46–57. Retrieved 2008-03-07.
- ^ Rasmussen, N. (2001). "Evolving Scientific Epistemologies and the Artifacts of Empirical Philosophy of Science: A Reply Concerning Mesosomes" (PDF). Biology and Philosophy. 16 (5): 627–652. Retrieved 2008-03-07.