Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
27
pubmed:dateCreated
1985-12-20
pubmed:abstractText
Acanthamoeba actin is the only actin sequenced to date that has neither an NH2-terminal Ac-Asp nor Ac-Glu residue. The protein begins with an Ac-Gly-Asp and is coded for by a gene that specifies a polypeptide beginning Met-Gly-Asp. Thus, the Acanthamoeba actin gene would appear to specify a class II actin with the usual NH2-terminal Cys replaced with a Gly. Previous studies (Rubenstein, P. A., and Martin, D. J. (1983) J. Biol. Chem. 258, 11354-11360) revealed that for class II actins the Met is probably removed early in translation and the Cys is removed post-translationally as an Ac-Cys residue. Two possibilities might explain why Acanthamoeba actin is not processed in a similar fashion. Either Ac-Gly is not a substrate for the enzyme or the enzyme is absent from the organism. To test these alternatives, Acanthamoeba actin was labeled in vivo with [35S]methionine and incubated with processing enzyme from rat liver, rabbit reticulocytes, and Dictyostelium. In no case did the processing reaction occur, indicating that Ac-Gly is not recognized by the enzyme as a substrate. Furthermore, we could not reproducibly detect the presence of a processing enzyme in Acanthamoeba. We were, however, able to show the presence of such an enzyme in Dictyostelium, the first demonstration of this activity in a lower eukaryote.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
260
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
14857-61
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Lack of NH2-terminal processing of actin from Acanthamoeba castellanii.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't