Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-11-9
pubmed:abstractText
Ecological studies have indicated that relative abundances of Gammaproteobacteria methanotrophs (Gamma-MOB) vs. Alphaproteobacteria methanotrophs (Alpha-MOB) in nitrogen (N) impacted soils are dictated in part by their abilities to tolerate inhibitory effects of ammonium and nitrite. In particular, ammonia is a cometabolic substrate and competitive inhibitor of methane monooxygenase. The rates of ammonia and hydroxylamine oxidation and inhibition of methane-oxidizing activity by ammonium and nitrite were compared among two Gamma-MOB and two Alpha-MOB to determine whether methanotrophs of the same class shared similar physiological profiles. Each isolate exhibited unique K(m(app)) for ammonia and V(max) for nitrite production with or without reductant (methane or sodium formate). The rates of nitrite production from hydroxylamine followed similar trends to rates of ammonia oxidation, indicating that hydroxylamine-oxidizing enzymes were central participants in the ammonia-oxidizing pathway. Methylomonas methanica was incapable of either ammonia or hydroxylamine oxidation. A broad range of sensitivities to ammonium and nitrite inhibition were measured with little consistency between isolates of the same class. The results indicate that physiological responses, and perhaps environmental adaptations, to N compounds are organism specific for methanotrophs.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1574-6968
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
297
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
131-6
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Ammonia cometabolism and product inhibition vary considerably among species of methanotrophic bacteria.
pubmed:affiliation
Department of Environmental Sciences, University of California, Riverside, CA, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't