Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.7 (DNA polymerase)
 17,007 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A sensitive and specific PCR method to detect Treponema pallidum in clinical specimens was developed. PCR primers were designed based on two unique features of the DNA polymerase I gene (polA). The first distinctive characteristic is that the region codes for a high cysteine content and has low homology with similar regions of DNA polymerase I gene from known microorganisms. The second unique feature is the presence of four insertions in the gene. PCR tests using primers designed on the basis these regions reacted with various pathogenic T. pallidum subspecies but did not react with nonpathogenic treponemal species or other spirochetes. An additional 59 species of bacteria and viruses, including those that cause genital ulcers, tested negative. This PCR method is extremely robust and sensitive. The detection limit is about 10 to 25 organisms when analyzed on gel. However, the analytic sensitivity can be increased by at least 1 log, to a detection limit of a single organism, when the ABI 310 Prism Genetic Analyzer is used to detect fluorescence-labeled amplicons. We further used this test in a clinical setting and compared the results with results from a previously reported multiplex-PCR test (for T. pallidum, Haemophilus ducreyi, and herpes simplex virus). We tested 112 genital ulcer specimens by the polA PCR, obtaining a sensitivity of 95.8% and a specificity of 95.7%. These results suggest that the polA PCR is applicable as a routine clinical diagnostic test for syphilis.
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PMID:New tests for syphilis: rational design of a PCR method for detection of Treponema pallidum in clinical specimens using unique regions of the DNA polymerase I gene. 1132 18

The beta-lactamase-producing Asia-type plasmid pJD4 of Neisseria gonorrhoeae is a 7.4-kb, broad-host-range plasmid. It is part of a family of plasmids which are structurally related yet vary in size, found in both N. gonorrhoeae and Haemophilus ducreyi. Branch-point analysis by electron microscopy indicates that pJD4 carries three clustered but distinguishable origins of replication, which we named ori1, ori2, and ori3. Although pJD4 belongs to incompatibility (Inc) group W, it also carries a silent IncFII determinant which is expressed when ori2 and ori3 are absent. The Africa-type plasmid pJD5, a naturally occurring deletion derivative of pJD4, carries only ori1, belongs to the IncFII group, and, in contrast to pJD4, requires DNA polymerase I (Pol I) for replication. Plasmids constructed from pJD4 which lack ori1 but carry ori2 and ori3 do not require Pol I and are incompatible with IncW plasmids, suggesting that the ori2 or ori3 region contains the IncW determinant. We have cloned a replication initiation protein (RepB) that is necessary for ori2 and ori3 to function. This Rep protein is distinct from RepA, which is necessary for ori1. Thus, pJD4 is unique because it is the smallest plasmid characterized containing three origins of replication and two unique Rep proteins.
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PMID:Multiple origins and replication proteins influence biological properties of beta-lactamase-producing plasmids from Neisseria gonorrhoeae. 1154 7