Time-dependent expression and processing of a hypothetical protein of possible importance for regulation of the Chlamydia pneumoniae developmental cycle

Chlamydia pneumoniae is an obligate intracellular human pathogen infesting epithelial cells of the upper respiratory tract. it is a Gram-negative bact eria and has a unique biphasic developmental cycle. In this study, we use t wo-dimensional gel electrophoresis in combination with radioactive labeling to investigate time-dependent expression and processing of C. pneumoniae p roteins. We report on (ij the identification of a hypothetical protein whic h is expressed late in the developmental cycle and subsequently processed; we speculate that this protein may be of importance for the developmental c ycle of Chlamydia; (ii) the identification of the major outer membrane prot ein in three different variants, which may all be present in vivo.