Linked Life Data

38850

Source:http://linkedlifedata.com/resource/pubmed/id/38850

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1979-11-29
pubmed:abstractText
A strain of the obligate anaerobe, Eubacterium lentum, isolated from human feces, catalyzes the 21-dehydroxylation of 11-deoxycorticosterone to progesterone. A quantitative radiochromatographic assay was developed to measure 21-dehydroxylase activity in cell extracts. Maximum enzyme activity in cell extracts required both a reduced pyridine nucleotide and an oxidized flavin coenzyme. However, photochemically reduced flavin (FMNH2) could replace the requirement for NAD(P)H plus oxidized flavin. NAD(P)H : flavin (either FMN or FAD) oxidoreductase activity was detected spectrophotometrically in cell extracts assayed under anaerobic conditions. 21-Dehydroxylase was active from pH 5.4 to 8.5 with an apparent optimum between 6.4 and 6.8 using mixtures of NADH plus FMN as coenzymes. The substrate concentration at half-maximal reaction velocity was 8.0 microM and a specific acitivity of 5.8 nmol [3H]progesterone formed . h-1 . mg-1 protein was determined using [3th]deoxycorticosterone as substrate. Atabrine, rotenone, acriflavin, and 2,4-dinitrophenol (all at 1 mM) inhibited 21-dehydroxylase activity in cell extracts by 25, 24, 35 and 84%, respectively. These results suggest that 21-dehydrogenase may be coupled to a NAD(P)H : flavin oxidoreductase system in E. lentum.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
27
pubmed:volume
574
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
154-63
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1979
pubmed:articleTitle
Characterization of a C21 neutral steroid hormone transforming enzyme, 21-dehydroxylase, in crude cell extracts of Eubacterium lentum.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.