ribB and ribBA genes from Acidithiobacillus ferrooxidans: expression levels under different growth conditions and phylogenetic analysis

Autor(es)

Knegt, Fabio H. P. ^[1] ; Mello, Luciane V. ^[2] ; Reis, Fernanda C. ^[1] ; Santos, Marcos T. ^[1] ; Vicentini, Renato ^[3] ; Ferraz, Lucio F. C. ^[1] ; Ottoboni, Laura M. M. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Ctr Biol Mol & Engn Genet, BR-13083875 Campinas, SP - Brazil

^[2] Univ Liverpool, NW Inst BioHlth Informat, Liverpool L69 7ZB, Merseyside - England

^[3] Univ Estadual Campinas, Dept Genet & Evolucao, Inst Biol, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Research in Microbiology; v. 159, n. 6, p. 423-431, JUL-AUG 2008.
• Citações Web of Science: 5

Resumo

Acidithiobacillus ferrooxidans is a Gram-negative, chemolithoautotrophic bacterium involved in metal bioleaching. Using the RNA arbitrarily primed polymerase chain reaction (RAP-PCR), we have identified several cDNAs that were differentially expressed when A. ferrooxidans LR was submitted to potassium- and phosphate-limiting conditions. One of these cDNAs showed similarity with ribB. An analysis of the A. ferrooxidans ATCC 23270 genome, made available by The Institute for Genomic Research, showed that the ribB gene was not located in the rib operon, but a ribBA gene was present in this operon instead. The ribBA gene was isolated from A. ferrooxidans LR and expression of both ribB and ribBA was investigated. Transcript levels of both genes were enhanced in cells grown in the absence of K2HPO4, in the presence of zinc and copper sulfate and in different pHs. Transcript levels decreased upon exposure to a temperature higher than the ideal 30 degrees C and at pH 1.2. A comparative genomic analysis using the A. ferrooxidans ATCC 23270 genome revealed similar putative regulatory elements for both genes. Moreover, an RFN element was identified upstream from the ribB gene. Phylogenetic analysis of the distribution of RibB and RibBA in bacteria showed six different combinations. We suggest that the presence of duplicated riboflavin synthesis genes in bacteria must provide their host with some benefit in certain stressful situations. (C) 2008 Elsevier Masson SAS. All fights reserved. (AU)

• Processo FAPESP: 01/12517-0 - Identificacao e caracterizacao de genes em acidithiobacillus ferrooxidans submetida ao estresse induzida pela privacao de fosfato.
• Beneficiário: Fabio Henrique Pfeilsticker de Knegt
• Modalidade de apoio: Bolsas no Brasil - Mestrado