Genome sequencing revealed that all six chlamydiae genomes contain three groEL-like genes (groEL1, groEL2, and groEL3). Phylogenetic analysis of groEL1, groEL2, and groEL3 indicates that these genes are likely to have been present in chlamydiae since the beginning of the lineage. Comparison of deduced amino acid sequences of the three groEL genes with those of other organisms showed high homology only for groEL1, although comparison of critical amino acid residues that are required for polypeptide binding of the Escherichia coli chaperonin GroEL revealed substantial conservation in all three chlamydial GroELs. This was further supported by three-dimensional structural predictions. All three genes are expressed constitutively throughout the developmental cycle of Chlamydia trachomatis, although groEL1 is expressed at much higher levels than are groEL2 and groEL3. Transcription of groEL1, but not groEL2 and groEL3, was elevated when HeLa cells infected with C. trachomatis were subjected to heat shock. Western blot analysis with polyclonal antibodies raised against recombinant GroEL1, GroEL2, and GroEL3 demonstrated the presence of the three proteins in C. trachomatis elementary bodies, with GroEL1 being present in the largest amount. Only C. trachomatis groEL1 and groES together complemented a temperature-sensitive E. coli groEL mutant. Complementation did not occur with groEL2 or groEL3 alone or together with groES. The role for each of the three GroELs in the chlamydial developmental cycle and in disease pathogenesis requires further study.The group I chaperonins, such as the GroEL protein of Escherichia coli and Hsp60 of eukaryotic mitochondria and plant chloroplasts, are a ubiquitous family of abundant proteins. These proteins play an essential role in ensuring that genome encoded proteins are expressed as fully functional molecules. In E. coli, homopolymers of GroEL interact with a ring-shaped cofactor composed of septamers of GroES or Hsp10 that forms the lid on an Anfinsen protein folding cage in which polypeptide substrates are assisted in folding into the correct three-dimensional (3-D) structure (24, 39). GroEL and GroES are present in the cytoplasm of unstressed E. coli cells, and both proteins are essential for bacterial growth at all temperatures (11). GroEL expression increases during a variety of conditions such as heat shock, nutrient deprivation, infection, and inflammatory reaction and functions to stabilize cellular proteins (40). GroEL proteins are highly conserved in sequence among bacteria and are recognized in hosts by Toll-like receptors as part of an innate defense system (38). GroELs are implicated in bacterial disease pathogenesis (41), and antibodies to chlamydial GroEL have been strongly associated with chlamydial disease sequelae (4). The mechanistic explanation underlying this epidemiological correlation remains undefined. We therefore undertook detailed bioinformatic, genetic, and immunologic studies of the three chlamydial groEL genes and proteins revealed during whole genome seque...
Six years after the first edition of The Guideline for Gynecological Practice, which was jointly edited by The Japan Society of Obstetrics and Gynecology and The Japan Association of Obstetricians and Gynecologists, the third revised edition was published in 2017. The 2017 Guidelines includes 10 additional clinical questions (CQ), which brings the total to 95 CQ (12 on infectious disease, 28 on oncology and benign tumors, 27 on endocrinology and infertility and 28 on healthcare for women). Currently a consensus has been reached on the Guidelines and therefore the objective of this report is to present the general policies regarding diagnostic and treatment methods used in standard gynecological outpatient care that are considered appropriate. At the end of each answer, the corresponding recommendation level (A, B, C) is indicated.
The mechanism and inhibitors of Chlamydia trachomatis serovar L2 infection of eukaryotic host cells were studied using a tissue culture model infection system. Potent inhibition of infectivity was observed when elementary bodies (EBs) were exposed to heparin or when HeLa 229 cells were treated with heparinase. No significant inhibition was seen the other way around. The same potent inhibition was observed when EBs were exposed to chemically 2-O-desulfated heparin (2-ODS heparin), which is composed of repeating disaccharide units of IdoA-GlcNS(6S), but not when exposed to chemically 6-ODS heparin or completely desulfated and N-resulfated heparin, which is composed of repeating disaccharide units of IdoA(2S)-GlcNS or IdoA-GlcNS, respectively. The inhibitory effects of 2-ODS heparin could be seen only with oligosaccharides longer than dodecasaccharides. The mutant Chinese hamster ovary (CHO) cell line 677, which is deficient in the biosynthesis of heparan sulfate, was less sensitive to C. trachomatis infection than were wild-type CHO cells. F-17 cells, deficient in 2-O-sulfation of heparan sulfate, had the same sensitivity to infection as wild-type CHO cells did. These data suggest that infection of host cells by EBS results from the specific binding of ligand molecules with affinity for heparin on the EB surface to heparan sulfate proteoglycans on the host cell surface. This binding may depend on host cell heparan sulfate chains that are 6-O-sulfated and longer than dodecasaccharides. The 2-ODS heparin oligosaccharides may be a potential agent for the prevention of C. trachomatis infection.
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