High relatedness selects against hypermutability in bacterial metapopulations

Proceedings of the Royal Society B: Biological Sciences - Tập 274 Số 1615 - Trang 1341-1347 - 2007
Freya Harrison1, Angus Buckling1
1Department of Zoology, University of OxfordSouth Parks Road, Oxford OX1 3PS, UK

Tóm tắt

Mutation rate and cooperation have important ecological and evolutionary consequences and, moreover, can affect pathogen virulence. While hypermutability accelerates adaptation to novel environments, hypermutable lineages (‘mutators’) are selected against in well-adapted populations. Using the model organismPseudomonas aeruginosa, we previously demonstrated a further potential disadvantage to hypermutability, namely, that it can accelerate the breakdown of cooperation. We now investigate how this property of mutators can affect their persistence in metapopulations. Mutator and wild-type bacteria were competed for 250 generations in globally competing metapopulations, imposing conditions of high or low intra-deme relatedness. High relatedness favours cooperating groups, so we predicted that mutators should achieve lower equilibrium frequencies under high relatedness than under low relatedness. This was observed in our study. Consistent with our hypothesis, there was a positive correlation between mean mutator and cheat frequencies. We conclude that when dense population growth requires cooperation, and when cooperation is favoured (high relatedness), demes containing high frequencies of mutators are likely to be selected against because they also contain high frequencies of non-cooperating cheats. We have also identified conditions where mutator lineages are likely to dominate metapopulations; namely, when low relatedness reduces kin selection for cooperation. These results may help to explain clinical distributions of mutator bacteria.

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Tài liệu tham khảo

10.1002/(SICI)1099-0496(199605)21:5<267::AID-PPUL1>3.0.CO;2-K

Bergan T, 1975, Epidemiological markers for Pseudomonas aeruginosa. 6. Relationship between concomitant non-mucoid and mucoid strains from the respiratory tract in cystic fibrosis, Acta Pathol. Microbiol. Scand. Suppl, 83, 553

10.1016/j.cub.2006.08.068

10.1016/S0966-842X(02)02413-7

10.1016/S0140-6736(96)05169-0

10.1128/AAC.49.6.2276-2282.2005

10.1099/00221287-148-5-1247

10.1126/science.283.5400.404

10.1007/s002030100278

Frank S. A. 1998 Foundations of social evolution . Monographs in behavior and ecology. Princeton NJ: Princeton University Press.

Funchain P, 2000, The consequences of growth of a mutator strain of Escherichia coli as measured by loss of function among multiple gene targets and loss of fitness, Genetics, 154, 959, 10.1093/genetics/154.3.959

10.1016/S0140-6736(01)05742-7

10.1126/science.1056421

10.1128/AAC.46.3.863-865.2002

10.1038/nature02744

10.1183/09031936.01.17202810

10.1016/0022-5193(64)90038-4

10.1016/j.cub.2005.09.048

Harrison F. & Buckling A. In preparation. Wider access to the adaptive landscape facilitates social cheating in a bacterial mutator.

10.1186/1741-7007-4-21

Ishii K, 1989, Evolutionarily stable mutation rate in a periodically changing environment, Genetics, 121, 163, 10.1093/genetics/121.1.163

10.1046/j.1365-2958.2003.03261.x

10.1099/mic.0.28418-0

10.1126/science.274.5290.1208

10.1136/thx.53.5.432

10.1128/CMR.15.2.194-222.2002

10.1128/IAI.64.2.518-523.1996

10.1080/09674845.2005.11732707

10.1067/mpd.2001.112897

10.1126/science.288.5469.1251

10.1128/AAC.48.11.4226-4233.2004

10.1016/S0960-9822(99)80230-9

10.1016/j.tree.2006.03.018

10.1016/S1526-0542(04)90065-6

10.1128/JB.187.14.4908-4920.2005

10.1128/AAC.46.11.3540-3548.2002

10.1016/0003-2697(87)90612-9

10.1073/pnas.0602138103

10.1128/JB.187.6.2138-2147.2005

10.1038/42701

10.1002/1521-1878(200012)22:12<1057::AID-BIES3>3.0.CO;2-W

10.1378/chest.114.3.814

10.1164/ajrccm.160.3.9811018

10.1038/42696

10.1111/j.1574-6968.1999.tb13661.x

10.1007/BF00328720

10.1098/rspb.2002.2209

10.1038/nrmicro1461

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Proceedings of the Royal Society B: Biological Sciences

Tập 274 Số 1615

1341-1347

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