Heat and phosphate starvation effects on the proteome, morphology and chemical composition of the biomining bacteria Acidithiobacillus ferrooxidans

Autor(es)

Ribeiro, Daniela A. ^[1] ; Maretto, Danilo A. ^[2] ; Nogueira, Fabio C. S. ^[3] ; Silva, Marcio J. ^[1] ; Campos, Francisco A. P. ^[4] ; Domont, Gilberto B. ^[3] ; Poppi, Ronei J. ^[2] ; Ottoboni, Laura M. M. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas UNICAMP, CBMEG, BR-13083875 Campinas, SP - Brazil

^[2] Univ Estadual Campinas UNICAMP, Inst Quim, BR-13083970 Campinas, SP - Brazil

^[3] Univ Fed Rio de Janeiro, Inst Quim, Dept Bioquim, BR-21941909 Rio De Janeiro - Brazil

^[4] Univ Fed Ceara, Dept Bioquim & Biol Mol, BR-60455900 Fortaleza, Ceara - Brazil

• Tipo de documento: Artigo Científico
• Fonte: WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY; v. 27, n. 6, p. 1469-1479, JUN 2011.
• Citações Web of Science: 9

Resumo

Acidithiobacillus ferrooxidans is a Gram negative, acidophilic, chemolithoautotrophic bacterium that plays an important role in metal bioleaching. During bioleaching, the cells are subjected to changes in the growth temperature and nutrients starvation. The aim of this study was to gather information about the response of the A. ferrooxidans Brazilian strain LR to K(2)HPO(4) starvation and heat stress through investigation of cellular morphology, chemical composition and differential proteome. The scanning electron microscopic results showed that under the tested stress conditions, A. ferrooxidans cells became elongated while the Fourier transform infrared spectroscopy (FT-IR) analysis showed alterations in the wavenumbers between 850 and 1,275 cm(-1), which are related to carbohydrates, phospholipids and phosphoproteins. These findings indicate that the bacterial cell surface is affected by the tested stress conditions. A proteomic analysis, using 2-DE and tandem mass spectrometry, enabled the identification of 44 differentially expressed protein spots, being 30 due to heat stress (40A degrees C) and 14 due to K(2)HPO(4) starvation. The identified proteins belonged to 11 different functional categories, including protein fate, energy metabolism and cellular processes. The upregulated proteins were mainly from protein fate and energy metabolism categories. The obtained results provide evidences that A. ferrooxidans LR responds to heat stress and K(2)HPO(4) starvation by inducing alterations in cellular morphology and chemical composition of the cell surface. Also, the identification of several proteins involved in protein fate suggests that the bacteria cellular homesostasis was affected. In addition, the identification of proteins from different functional categories indicates that the A. ferrooxidans response to higher than optimal temperatures and phosphate starvation involves global changes in its physiology. (AU)

• Processo FAPESP: 02/07642-3 - Expressao diferencial de genes em acidithiobacillus ferrooxidans submetida ao estresse induzido por ph, temperatura e privacao de fosfato.
• Beneficiário: Laura Maria Mariscal Ottoboni
• Modalidade de apoio: Auxílio à Pesquisa - Regular