The <i>Chlamydia pneumoniae</i> Type III Secretion-Related <i>lcrH</i> Gene Clusters Are Developmentally Expressed Operons

Abstract

Two chlamydial homologues of the Yersinia lcrH chaperone for type III secretion system structural components are present within separate gene clusters. Quantitative transcriptional analyses demonstrated that each cluster is differentially regulated and expressed as an operon using major sigma factor elements, suggesting the presence of more elaborate developmental regulation mechanisms in chlamydiae.