« Previous AbstractRegulation of the pAD1 sex pheromone response in Enterococcus faecalis: construction and characterization of lacZ transcriptional fusions in a key control region of the plasmid    Next AbstractThe RepA_N replicons of Gram-positive bacteria: a family of broadly distributed but narrow host range plasmids »

J Bacteriol

Title:		"Regulation of the pAD1 sex pheromone response in Enterococcus faecalis: effects of host strain and traA, traB, and C region mutants on expression of an E region pheromone-inducible lacZ fusion"
Author(s):		Weaver KE; Clewell DB;
Address:		"Department of Oral Biology, School of Dentistry, University of Michigan, Ann Arbor 48109"
Journal Title:		J Bacteriol
Year:		1990
Volume:		172
Issue:		5
Page Number:		2633 - 2641
DOI:		10.1128/jb.172.5.2633-2641.1990
ISSN/ISBN:		0021-9193 (Print) 1098-5530 (Electronic) 0021-9193 (Linking)
Abstract:		"Pheromone-induced conjugal transfer of the hemolysin-bacteriocin plasmid pAD1 of Enterococcus faecalis is regulated by a cluster of determinants designated traA, traB, and regions C and E. The E region is believed to include a positive regulator that controls many structural genes related to conjugation. The pheromone-inducible Tn917-lac fusion NR5, located in the E region, is regulated by the products of traA, traB, and the C region. To more closely examine the effects of these genes on the induction of E region products, inserts in each of these genes were combined with the NR5 fusion in a novel approach involving triparental matings with a pAD1 miniplasmid and recombinational mutagenesis. Results indicate that (i) the traA gene product is a key repressor of the pheromone response; (ii) the traB gene product, in cooperation with a gene within or regulated by the E region, controls pheromone shutdown; (iii) a primary function of the C region gene product is in pheromone sensing, with secondary functions in pheromone shutdown and negative regulation; and (iv) the host in which the plasmid resides has a dramatic effect on the regulation of the NR5 fusion in traB and C region mutants. Numerous parallels were observed between the regulation of the NR5 fusion and the regulation of the aggregation and transfer response. These parallels aided in further defining the functions of particular regulatory determinants as well as further establishing the link between the regulation of the E region and the regulation of the aggregation and transfer response"
Keywords:		"Cloning, Molecular Conjugation, Genetic DNA Transposable Elements Enterococcus faecalis/*genetics/growth & development Genes, Bacterial *Genes, Regulator Multigene Family Phenotype Pheromones/*metabolism Plasmids Transcription, Genetic;"
Notes:		"MedlineWeaver, K E Clewell, D B eng AI 10318/AI/NIAID NIH HHS/ GM33956/GM/NIGMS NIH HHS/ Research Support, U.S. Gov't, P.H.S. 1990/05/01 J Bacteriol. 1990 May; 172(5):2633-41. doi: 10.1128/jb.172.5.2633-2641.1990"