Changes in morphology, cell wall composition and soluble proteome in Rhodobacter sphaeroides cells exposed to chromate.
The response of the carotenoidless Rhodobacter sphaeroides mutant R26 to chromate stress under photosynthetic conditions is investigated by biochemical and spectroscopic measurements, proteomic analysis and cell imaging. Cell cultures were found able to reduce chromate within 3-4 days. Chromate induces marked changes in the cellular dimension and morphology, as revealed by atomic force microscopy, along with compositional changes in the cell wall revealed by infrared spectroscopy. These effects are accompanied by significant changes in the level of several proteins: 15 proteins were found up-regulated and 15 down-regulated. The protein content found in chromate exposed cells is in good agreement with the biochemical, spectroscopic and microscopic results. Moreover at the present stage no specific chromate-reductase could be found in the soluble proteome, indicating that detoxification of the pollutant proceeds via aspecific reductants.
CNR-IPCF, Consiglio Nazionale delle Ricerche, Istituto per i Processi Chimico Fisici, Via Orabona 4, 70125, Bari, Italy.
Francesca
F
Italiano
Sara
S
Rinalducci
Angela
A
Agostiano
Lello
L
Zolla
Francesca
F
De Leo
Luigi R
LR
Ceci
Massimo
M
Trotta
D001426:Bacterial Proteins / Q000302:isolation & purification / Q000378:metabolism; D001673:Biodegradation, Environmental; D002473:Cell Wall / Q000737:chemistry / Q000187:drug effects; D002840:Chromates / Q000378:metabolism / Q000633:toxicity*; D004785:Environmental Pollutants / Q000633:toxicity; D018625:Microscopy, Atomic Force; D009154:Mutation; D010084:Oxidation-Reduction; D010788:Photosynthesis / Q000187:drug effects; D020543:Proteome / Q000187:drug effects / Q000302:isolation & purification; D012242:Rhodobacter sphaeroides / Q000166:cytology / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared
D001426:Bacterial Proteins; D002840:Chromates; D004785:Environmental Pollutants; D020543:Proteome