Linked Life Data

9930988

Source:http://linkedlifedata.com/resource/pubmed/id/9930988

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-2-19
pubmed:abstractText
Rhodothermus marinus, a thermohalophilic bacterium, has a unique electron-transfer chain, containing, besides a cbb3 and a caa3 terminal oxidases, a novel cytochrome bc complex [Pereira, M. M., Carita, J. N., and Teixeira, M. (1999) Biochemistry 38, 1268-1275]. The membrane-bound iron-sulfur centers of this bacterium were studied by electron paramagnetic resonance (EPR) spectroscopy, leading to the identification of its main electron-transfer complexes. The resonances typical for the Rieske-type centers are not detected. Clusters S1 and S3 from succinate dehydrogenase were identified; interestingly, center S3 is shown to be present in two different conformations, with g values at 2.035, 2.009, and 2.001 and at 2.025, 2.002, and 2.000. Upon addition of NADH and dithionite, EPR signals assigned to resonances characteristic of binuclear and tetranuclear clusters develop and are attributed to the iron-sulfur centers of complexes I and II. A high-potential iron-sulfur protein- (HiPIP-) type center previously detected in the membranes of this bacterium [Pereira et al. (1994) FEBS Lett. 352, 327-330] is shown to belong indeed to a canonical HiPIP. This protein was purified and extensively characterized. It is a small water-soluble protein of approximately 10 kDa, containing a single [4Fe-4S]3+/2+ cluster. The reduction potential, determined by EPR redox titrations in intact and detergent-solubilized membranes as well as by cyclic voltammetry in solution, has a pH-independent value of 260 +/- 20 mV, in the range 6-9. In vitro reconstitution of the R. marinus electron-transfer chain shows that the HiPIP plays a fundamental role in the chain, as the electron shuttle between R. marinus cytochrome bc complex and the caa3 terminal oxidase, being thus simultaneously identified a HiPIP reductase and a HiPIP oxidase.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
26
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1276-83
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Membrane-bound electron transfer chain of the thermohalophilic bacterium Rhodothermus marinus: characterization of the iron-sulfur centers from the dehydrogenases and investigation of the high-potential iron-sulfur protein function by in vitro reconstitution of the respiratory chain.
pubmed:affiliation
Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, APT 127, 2780 Oeiras, Portugal.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't