Leptospira interrogans serovar Copenhageni Harbors Two lexA Genes Involved in SOS Response

Autor(es)

Fonseca, Luciane S. ^{[1, 2]} ; da Silva, Josefa B. ^[2] ; Milanez, Juliana S. ^[2] ; Monteiro-Vitorello, Claudia B. ^[3] ; Momo, Leonardo ^[4] ; de Morais, Zenaide M. ^[5] ; Vasconcellos, Silvio A. ^[5] ; Marques, Marilis V. ^[6] ; Ho, Paulo L. ^{[1, 2]} ; da Costa, Renata M. A. ^[4]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Quim, Dept Bioquim, BR-01498 Sao Paulo - Brazil

^[2] Inst Butantan, Ctr Biotecnol, Sao Paulo - Brazil

^[3] Escola Super Agr Luis Dequeiroz, Dept Genet, Piracicaba - Brazil

^[4] Univ Fed ABC, Ctr Ciencias Nat & Humanas, Santo Andre - Brazil

^[5] Univ Sao Paulo, Dept Med Vet Prevent & Saude Anim, BR-05508 Sao Paulo - Brazil

^[6] Univ Sao Paulo, Dept Microbiol, Inst Ciencias Biomed, BR-05508 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PLoS One; v. 8, n. 10 OCT 3 2013.
• Citações Web of Science: 9

Resumo

Bacteria activate a regulatory network in response to the challenges imposed by DNA damage to genetic material, known as the SOS response. This system is regulated by the RecA recombinase and by the transcriptional repressor lexA. Leptospira interrogans is a pathogen capable of surviving in the environment for weeks, being exposed to a great variety of stress agents and yet retaining its ability to infect the host. This study aims to investigate the behavior of L. interrogans serovar Copenhageni after the stress induced by DNA damage. We show that L. interrogans serovar Copenhageni genome contains two genes encoding putative LexA proteins (lexA1 and lexA2) one of them being potentially acquired by lateral gene transfer. Both genes are induced after DNA damage, but the steady state levels of both LexA proteins drop, probably due to auto-proteolytic activity triggered in this condition. In addition, seven other genes were up-regulated following UV-C irradiation, recA, recN, dinP, and four genes encoding hypothetical proteins. This set of genes is potentially regulated by LexA1, as it showed binding to their promoter regions. All these regions contain degenerated sequences in relation to the previously described SOS box, TTTGN (5)CAAA. On the other hand, LexA2 was able to bind to the palindrome TTGTAN (10)TACAA, found in its own promoter region, but not in the others. Therefore, the L. interrogans serovar Copenhageni SOS regulon may be even more complex, as a result of LexA1 and LexA2 binding to divergent motifs. New possibilities for DNA damage response in Leptospira are expected, with potential influence in other biological responses such as virulence. (AU)

• Processo FAPESP: 09/17123-2 - Identificação e caracterização molecular de genes envolvidos na resposta do agente infeccioso Leptospira interrogans ao estresse oxidativo
• Beneficiário: Renata Maria Augusto da Costa
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 10/51365-0 - Contribuição ao conhecimento de Leptospira interrogans serovar Copenhageni utilizando a informação genômica
• Beneficiário: Paulo Lee Ho
• Modalidade de apoio: Auxílio à Pesquisa - Temático