medigraphic.com
Centro de Investigaciones Regionales Dr. Hideyo Noguchi, Universidad Autónoma de Yucatán

2008, Number 3

<< Back Next >>

Rev Biomed 2008; 19 (3)

Damage and response to oxidative stress in anaerobic bacteria of the genus Bacteroides: antimicrobial resistance and virulence factors

Quesada-Gómez C

Language: Spanish
References: 16
Page: 162-168
PDF size: 114.18 Kb.


ABSTRACT

Some bacterial species such as Escherichia coli have tolerance features against oxygen reactive substance (ROS). One of the main products from oxidative damage to the DNA molecule in in vivo and in vitro is the 8-hydroxydeoxyguanosine (8OHdG), which could be used as a biological marker as result of such effect. The exposure of Prevotella to H2O2 in an atmosphere free of oxygen results in high levels of 8OHdG with a surviving rate of less than 1.0 %.
In anaerobic bacteria of clinical importance, mainly in those of the genus Bacteroides it has been observed that an increasing of the 8OHdG correlates with a lower surviving rate. Some of the responses to oxidative stress have been found in B. fragilis and the genes involved in ROS detoxification mechanism and DNA repair are katB (catalase), sod (superoxide dismutase), ahpCF (alquil-hydroperoxide reductase) and dps (DNA unspecific binding proteins).
In B. thetaiotaomicron recA- the sensitivity to oxygen is higher as compared with the wild type strain. It also shows higher resistance to metronidazol, one of the first choice antimicrobial used against anaerobic bacterial infections.
The oxidative stress has a negative effect on Bacteroides growth, however a group of genes known as oxidative stress response (OSR) allow this bacterial genus a significant aerotolerance, therefore, higher virulence ability as to cause infection in humans.
In this review, the mechanisms against the oxidative damage in the anaerobic bacterium Bacteroides are summarized. In addition, the protection events mentioned above are correlated with virulence of this anaerobe in human infections and with a possible relation with resistance to antimicrobials such as the metronidazol.


REFERENCES

  1. Rocha E, Selby T, Coleman J, Smith, J. Oxidative stress response in an anaerobe, Bacteroides fragilis: a role for catalase in protection against hydrogen peroxide. J Bacteriol 1996; 178:6895–03.

  2. Takeuchi T, Nakaya Y, Kato N, Watanabe K, Morimoto K. Induction of oxidative DNA damage in anaerobes. FEBS Letters 1999; 450:178–80.

  3. Rocha E, Herren C, Smalley D, Smith J. The complex oxidative stress response of Bacteroides fragilis: the role of OxyR in control of gene expression. Anaerobe 2003; 9:165–73.

  4. Smalley D, Rocha E, Smith J. Aerobic-type ribonucleotide reductase in the anaerobe Bacteroides fragilis. J Bacteriol 2002;184(4):895–903.

  5. Jordan A, Reichard P. Ribonucleotide reductases. Annu Rev Biochem 2002; 67:71–98.

  6. Falagas M, Siakavellas E. Bacteroides, Prevotella and Porphyromonas species. A review of antibiotic resistance and therapeutic options. Int J Antimicrob Ag 2000; 15:1–9.

  7. Edwards D. Nitrimidazole drugs – action and resistance mechanisms. J Antimicrob Chemoth 1993; 31:201–10.

  8. Pumbwe L., Glass D., Wexler H. Efflux pump overexpression in multiple-antibiotic-resistant mutants of Bacteroides fragilis. Antimicrob Agent Ch 2006; 50:3150–53.

  9. Lofmark S, Fang H, Hedberg M, Edlund C. Inducible metronidazole resistance and nim genes in clinical Bacteroides fragilis group isolates. Antimicrob Agent Ch 2005; 49:1253–56.

  10. Diniz C, Farias F, Carvalho M, Rocha E, Smith J. Differential gene expression in a Bacteroides fragilis metronidazol-resistant mutant. J Antimicrob Chemoth 2004; 54:100–08.

  11. Chang K-C, Ho S-W, Yang J-C, Wang J-T. Isolation of the genetic locus associated with metronidazole resistance in Helicobacter pylori. Biochem Bioph Res Co 1997; 236:785–88.

  12. Cooper A, Kalinowski A, Shoemaker N, Salyers A. Construction and characterization of Bacteroides thetaiotaomicron recA mutant: transfer of Bacteroides integrated conjugative elements in RecA independent. J Bacteriol 1997; 179:6221–27.

  13. Gallegos M, Scheilf R, Bairoch A, Hoffman K, Ramos J. AraC/XlyS family of transcriptional regulators. Microbiol Mol Biol R 1997; 61:393–410.

  14. Tanaka T, Horii T, Shibayama K. RobA-induced multiple antibiotic resistance largely depends on the activation of the AcrAB efflux. Microbiol Immunol 1997; 41:697–702.

  15. Casanueva A, Paul L, Patrick S, Abratt V. An AraC/XylsS family transcriptional regulator homologue from Bacteroides fragilis is associated with cell survival following DNA damage. FEMS Microbiol Lett 2008; 278:249–56.

  16. Keyer K, Gort A, Imlay J. Superoxide and the production of oxidative DNA damage. J Bacteriol 1995; 177:6782–90.




2020     |     www.medigraphic.com