Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0519030 (Klebsiella)
 21,988 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

6 beta-[(1-Substituted-4-pyridinio)amino]penam-3-carboxylates and 7 beta-[(1-substituted-4-pyridinio)amino]ceph-3-em-4-carboxylates have been found to be interesting new classes of antibacterial beta-lactams, readily available by SN2 Ar coupling of fluoro-substituted quaternized pyridines and appropriate amino lactam carboxylic acids. Compared to penicillin G, the penam 12c exhibited a spectrum extended to Gram-negative species, such as Escherichia, Shigella, Klebsiella and Enterobacter, offset by a loss of potency against Gram-positive species. Excluding Pseudomonas, many examples of the cephems showed excellent activity against the above Gram-negative organisms, and in some cases, such as 15i, the spectrum included good performance against the staphylococci and streptococci. With Serratia and many Proteus species, there was an adverse inoculum and medium effect which was not observed in the good Gram-positive reach of the cephem series.
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PMID:Quaternary heterocyclylamino beta-lactams: a generic alternative to the classical acylamino side chain. 706 25

Oligosaccharides embodying the S-maltosyl-6-thiomaltosyl structure have been readily synthesised by using convergent chemoenzymatic approaches. The key steps for the preparation of these molecules involved: 1) transglycosylation reactions of maltosyl fluorides onto suitable acceptors catalysed by the bacterial transglycosylase, cyclodextrin glycosyltransferase (CGTase), and 2) the SN2-type displacement of a 6-halide from acetylated acceptors by activated 1-thioglycoses. The target molecules, which were obtained in good overall yields, proved to be useful for investigating substrate binding in the active sites of several enzymes that act upon the alpha-1,6-linkage of pullulan and/or amylopectin. The compounds exhibit Ki values in the 2.5-1350 microM range with the different enzymes, and the highest affinity found by using these molecules was seen for the pullulanase from Bacillus acidopullulyticus. Both barley-malt limit dextrinase and pullulanase type II from Thermococcus hydrothermalis only recognised the longest linear thiooligosaccharide, while a branched heptasaccharide was the strongest inhibitor of pullulanase from Klebsiella planticola.
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PMID:Chemoenzymatic syntheses of linear and branched hemithiomaltodextrins as potential inhibitors for starch-debranching enzymes. 1256 17