Antibiotics, peptidoglycan synthesis and genomics: the chlamydial anomaly revisited

Abstract

Gump, D. W. (1996). Antimicrobial susceptibility testing for some atypical microorganisms : chlamydiae, mycoplasmas, rickettsia and spirochetes. In Antibiotics in Laboratovy Medicine, 4th edn, pp. 212-229. Edited by V. Lorian. Baltimore: Williams & Wilkins.

Functional and Biochemical Analysis of Chlamydia trachomatis MurC, an Enzyme Displaying UDP- N -Acetylmuramate:Amino Acid Ligase Activity

“…Thus, chlamydiae express penicillin-binding proteins (1,29), and transcripts of murA (encoding UDP-N-acetylglucosamine-enolpyruvate transferase) and murB (encoding UDP-N-acetylglucosamine-enolpyruvate reductase) have been detected during the chlamydial growth cycle (21; T. Hatch, presented at the Ninth International Symposium on Human Chlamydial Infection, 1998). Furthermore, genes for chlamydial penicillin-binding proteins have been cloned and expressed in Escherichia coli and Schizosaccharomyces pombe (3), and in vitro and in vivo functional activity of MurA from C. trachomatis has recently been demonstrated (21). The susceptibility of chlamydiae to penicillin, D-cycloserine, and bacitracin is also consistent with expression of peptidoglycan biosynthetic enzymes in these organisms and provides further evidence that peptidoglycan has some fundamental role in chlamydiae (3).…”

“…Despite the failure to detect peptidoglycan in chlamydiae, bioinformatic analysis of the Chlamydia trachomatis and Chlamydia pneumoniae genomes reveals a complete set of genes whose products are apparently capable of synthesizing peptidoglycan in these organisms (3,14,28). A number of these genes are known to be expressed in chlamydiae and encode functional products.…”

“…Furthermore, genes for chlamydial penicillin-binding proteins have been cloned and expressed in Escherichia coli and Schizosaccharomyces pombe (3), and in vitro and in vivo functional activity of MurA from C. trachomatis has recently been demonstrated (21). The susceptibility of chlamydiae to penicillin, D-cycloserine, and bacitracin is also consistent with expression of peptidoglycan biosynthetic enzymes in these organisms and provides further evidence that peptidoglycan has some fundamental role in chlamydiae (3). Nevertheless, the exact role of peptidoglycan in the metabolism and growth of chlamydiae remains obscure.…”

Is there a need for rescreening of patients treated for genital chlamydial infections?

“…Chlamydial organisms have the capability to synthesize peptidoglycan 34 . Electron microscopic studies have shown the development of atypical swollen RBs when exposed to penicillin.…”

Discovery and Validation of New Regulatory RNA Elements in Chlamydia trachomatis

“…Genome sequencing indicated that Chlamydia lack an identifiable ftsZ orthologue, which encodes a protein centrally involved in bacterial cell division and found in all other sequenced eubacteria. Another surprising finding in the genomic analyses was the presence of a complete set of genes for the synthesis, assembly, and degradation of peptidoglycan (PG) (Chopra et al, 1998;Stephens et al, 1998;Read et al, 2000;) and (Read et al, 2003) Numerous studies had reported that Chlamydia lacked peptidoglycan, with a single study reporting trace amounts in EBs (Su H., 1985). Similarly, attempts to identify peptidoglycan in RBs were unsuccessful (Barbour et al, 1982).…”