ISSN:
1662-8985
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Acidithiobacillus ferrooxidans, an acidophilic, chemolithotrophic, γ-proteobacterium, isinvolved in the bioleaching of metal sulfides. For this process, bacterial attachment to mineralsurface and biofilm development play a pivotal role. Generally, biofilm formation and production ofexopolysaccharides is regulated by the second messenger cyclic diguanylic acid (c-di-GMP) whosecellular level depends on the synthesis and degradation activities of diguanylate cyclase (DGCs,with GGDEF domain) and phosphodiesterase (PDE, with EAL or HD-GYP domains), respectively.The analysis of the genomic sequence of A. ferrooxidans ATCC 23270 allowed us to identify 5putative orfs encoding DGC and/or PDE-like proteins. Four of them encode for bifunctionalputative proteins with GGDEF and EAL domains and are named AFE_0053, AFE_1360,AFE_1373 and AFE_1379. The fifth one named AFE_1852 has an EAL domain. The putativeproteins also include PAS and GAF domains involved in signal transduction. These features suggestan involvement in signalling transduction through the metabolism of c-di-GMP. The amino acidsequences of these putative proteins were aligned with known DGCs and PDEs. Alignmentsindicate that AFE_1360 and AFE_1373 share more consensus sequences with active PDEs, whereasAFE_0053 and AFE_1379 do with active DGCs. On the other hand, in AFE_1852 some conservedresidues of known active PDEs are changed. RT-PCR-experiments revealed that the genes thatencode for these putative DGCs and/or PDEs are expressed by growth on two different substrates.These preliminary results suggest that A. ferrooxidans possesses a c-di-GMP pathway that should beinvolved in biofilm formation, as it occurs in many bacteria
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/39/transtech_doi~10.4028%252Fwww.scientific.net%252FAMR.20-21.551.pdf
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