Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1991-9-19
pubmed:abstractText
The seven members of the hok killer gene family in Gram-negative bacteria are described here. The members of this gene family have been sequenced and include hok/sok from plasmid R1, flm and srnB from plasmid F, pnd from plasmids R483 and R16, and gef and relF, which are located on the Escherichia coli chromosome. The killer proteins encoded by these loci are highly toxic polypeptides of 50 to 52 amino acids. The proteins kill the cells from the inside by interfering with a vital function in the cell membrane. On the basis of their relatedness, the killer proteins and their corresponding loci are divided into four subfamilies. The members of one subfamily, hok/sok and flm, mediate plasmid maintenance by killing plasmid-free cells. The pnd and srnB subfamilies were discovered through their abilities to cause membrane damage and degradation of stable RNA. gef and relF, which constitute the chromosomal subfamily, were found because of their sequence similarity at the DNA and protein levels with other members of the hok gene family. However, no function has been described for the proteins belonging to this subfamily. Although the four subfamilies are distantly related in terms of DNA and protein sequence similarity, the overall genetic organization of the different loci has been well conserved during evolution. The expression of all of the members of the hok gene family is regulated post-transcriptionally. Thus, the expression of the hok and flm genes is regulated by small antisense RNAs that inhibit the translation of the stable hok and flm mRNAs. On the basis of structural and functional similarities, we suggest that each of the related plasmid-encoded killer genes is regulated by antisense RNAs. The conservation of this widespread gene family in Gram-negative bacteria suggests that the genes are important to the genomes that carry them.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1043-4674
pubmed:author
pubmed:issnType
Print
pubmed:volume
2
pubmed:geneSymbol
ccd, cer, flm, flmB, flmC, gef, hok, hok/sok, lox, mok, orf69, par, pem, pnd, pndA, pndB, pndC, relF, sof, sok, sop, srnA, srnB, srnC
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
946-56
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
The hok killer gene family in gram-negative bacteria.
pubmed:affiliation
Department of Molecular Biology, Odense University, Denmark.
pubmed:publicationType
Journal Article, Comparative Study, Review, Research Support, Non-U.S. Gov't