TY - JOUR
T1 - Selenium is involved in regulation of periplasmic hydrogenase gene expression in Desulfovibrio vulgaris Hildenborough
AU - Valente, Filipa M A
AU - Almeida, Cláudia C.
AU - Pacheco, Isabel
AU - Carita, João
AU - Saraiva, Lígia M.
AU - Pereira, Inês A C
PY - 2006/5/1
Y1 - 2006/5/1
N2 - Desulfovibrio vulgaris Hildenborough is a good model organism to study hydrogen metabolism in sulfate-reducing bacteria. Hydrogen is a key compound for these organisms, since it is one of their major energy sources in natural habitats and also an intermediate in the energy metabolism. The D. vulgaris Hildenborough genome codes for six different hydrogenases, but only three of them, the periplasmic-facing [FeFe], [FeNi]1, and [FeNiSe] hydrogenases, are usually detected. In this work, we studied the synthesis of each of these enzymes in response to different electron donors and acceptors for growth as well as in response to the availability of Ni and Se. The formation of the three hydrogenases was not very strongly affected by the electron donors or acceptors used, but the highest levels were observed after growth with hydrogen as electron donor and lowest with thiosulfate as electron acceptor. The major effect observed was with inclusion of Se in the growth medium, which led to a strong repression of the [FeFe] and [NiFe]1 hydrogenases and a strong increase in the [NiFeSe] hydrogenase that is not detected in the absence of Se. Ni also led to increased formation of the [NiFe]1 hydrogenase, except for growth with H2, where its synthesis is very high even without Ni added to the medium. Growth with H2 results in a strong increase in the soluble forms of the [NiFe]1 and [NiFeSe] hydrogenases. This study is an important contribution to understanding why D. vulgaris Hildenborough has three periplasmic hydrogenases. It supports their similar physiological role in H2 oxidation and reveals that element availability has a strong influence in their relative expression.
AB - Desulfovibrio vulgaris Hildenborough is a good model organism to study hydrogen metabolism in sulfate-reducing bacteria. Hydrogen is a key compound for these organisms, since it is one of their major energy sources in natural habitats and also an intermediate in the energy metabolism. The D. vulgaris Hildenborough genome codes for six different hydrogenases, but only three of them, the periplasmic-facing [FeFe], [FeNi]1, and [FeNiSe] hydrogenases, are usually detected. In this work, we studied the synthesis of each of these enzymes in response to different electron donors and acceptors for growth as well as in response to the availability of Ni and Se. The formation of the three hydrogenases was not very strongly affected by the electron donors or acceptors used, but the highest levels were observed after growth with hydrogen as electron donor and lowest with thiosulfate as electron acceptor. The major effect observed was with inclusion of Se in the growth medium, which led to a strong repression of the [FeFe] and [NiFe]1 hydrogenases and a strong increase in the [NiFeSe] hydrogenase that is not detected in the absence of Se. Ni also led to increased formation of the [NiFe]1 hydrogenase, except for growth with H2, where its synthesis is very high even without Ni added to the medium. Growth with H2 results in a strong increase in the soluble forms of the [NiFe]1 and [NiFeSe] hydrogenases. This study is an important contribution to understanding why D. vulgaris Hildenborough has three periplasmic hydrogenases. It supports their similar physiological role in H2 oxidation and reveals that element availability has a strong influence in their relative expression.
UR - http://www.scopus.com/inward/record.url?scp=33646260195&partnerID=8YFLogxK
U2 - 10.1128/JB.188.9.3228-3235.2006
DO - 10.1128/JB.188.9.3228-3235.2006
M3 - Article
C2 - 16621815
AN - SCOPUS:33646260195
VL - 188
SP - 3228
EP - 3235
JO - Journal of Bacteriology
JF - Journal of Bacteriology
SN - 0021-9193
IS - 9
ER -