Journal of Biological Sciences1727-30481812-5719Asian Network for Scientific Information10.3923/jbs.2008.349.355drrA Gene Affects the Xanthomonas axonopodis pv. citri Response to Oxidative Stress]]>Cursino-SantosJeny Rachid MeneguimLuciana Leite Jr.Rui Pereira Martinez-RossiNilce Maria 2200882The deduced amino acid sequence of drrA gene (XAC3759) from Xanthomonas axonopodis pv. citri (Xac) is similar to a variety of earlier described functionally uncharacterized ABC (ATP-Binding Cassette) transporters. In order to investigate the biological process in which this gene is involved, we constructed a drrA deletion mutant strain and tested its susceptibility to drugs with different mechanisms of action and to oxidative stress and also its capability to infect Citrus sinensis. The results showed that Xac responses to seven drugs (tetracycline, penicillin, ampicillin, chloramphenicol, acriflavine, ethidium bromide and doxorubicin chloridrate) and to host infection are independent upon drrA expression. However, Northern Blot analyses revealed that drrA gene is induced as short response to H2O2 exposure, only at the early phase of bacterial growth. Furthermore, the drrA disruption rendered the mutant more sensitive to oxidative stress than the control strain, suggesting that this transporter plays an important role in modulating oxidative stress susceptibility in Xac. Also, the drrA gene is co-transcripted with two hypothetical ORFs (Open Read Frame) as an operon cluster (named here drrABC) when Xac wild type strain was submitted to oxidative stress. The sequence analysis and topology prediction of the deduced proteins from these two neighboring hypothetical ORFs (XAC3758 and XAC3757) show that they have 6 transmembrane segments which are characteristic of permeases, supporting the structure of ABC transporter systems with an ABC subunit and two permeases.]]>Ausubel, F., R. Brent, R.E. Kingston, D.D. Moore, J.G. Seidman, J.A. Smithand and K. Struhl, 1987Baldini, R.L., S.T. Tahara and Y.B. Rosato, 1999Xanthomonas campestris pv. glycines: The nucleotide sequence and its use as a cloning vector.]]>42126133Biemans-Oldehinkel, E., M.K. Doeven and B. Poolman, 200658010231035Bonas, U. and G. Van den Ackerveken, 199929498Brencic, A. and S.C. Winans,200569155194Burse, A., H. Weingart and M.S. Ullrich, 2004Erwinia amylovora.]]>174354Da Silva, A.C., J.A. Ferro, F.C. Reinach, C.S. Farah and L.R. Furlan et al.,2002Xanthomonas pathogens with differing host specificities.]]>417459463Daniels, M.J., C.E. Barber, P.C. Turner, M.K. Sawczyc, R.J. Byrde and AH. Fielding, 1984Xanthomonas campestris pv. campestris using the broad host range cosmid pLAFR1.]]>333233328Dassa, E. and P. Bouige, 2001152211229Farr, S.B. and T. Kogoma, 1991Escherichia coli and Salmonella typhimurium.]]>55561585Ferreira, H., F.J.A. Barrientos, R.L. Baldini and Y.B. Rosato, 1995Xanthomonas campestris.]]>43651655Fridovich, I., 19972), superoxide dismutases and related matters.]]>2711851518517Lamb, L. and R.A. Dixon, 199748251275Mehta, A. and R.P. Leite, 2001Xanthomonas axonopodis pv. aurantifolii strain C to sweet orange.]]>275356Mongkolsuk, S., J.M. Dubbs and P. Vattanaviboon, 2005Xanthomonas.]]>32687690Mulder, N.J., R. Apweiler, T.K. Attwood, A. Bairoch and D. Barrell et al.,200331315318Piddock, L.J., 20064629636Ren, Q., K.H. Kang and I.T. Paulsen, 200432284288Ren, Q. and I.T. Paulsen, 20051e27e27Sambrook, J., E.F. Fritsch and T.A. Maniatis,19892nd Edn.,Pages: 397Pages: 397Verniere, C.J., T.R. Gottwald and O. Pruvost, 2003Xanthomonas axonopodis pc. citri in various citrus plant tissues.]]>93832843White, T.J. and C.F. Gonzalez, 1991Xanthomonas campestris pv. oryzae.]]>81521524