Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0155339 (Brown)
 12,436 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A method is described which allows a large number of bacterial strains to be rapidly and easily screened for the presence of site-specific endonucleases. The method involves selective permeabilization of the bacterial cell and analysis of the exuded material. Type II restriction endonucleases from cyanobacteria and Gram-negative eubacteria have been detected and new enzymes have been found. The method should be widely applicable and easy to modify for use in genera other than those tested. Three-site-specific endonuclease activities, detected by this method in Aphanothece halophytica PCC 7412, were purified and their recognition and cleavage specificities were determined AhaI and AhaII recognise and cleave the same DNA sequences as CauII and AcyI respectively; the specificity of AhaIII (TTT decreases AAA) has been reported previously (Whitehead and Brown, 1982, FEBS Letters 143:296-300).
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PMID:A simple and rapid method for screening bacteria for type II restriction endonucleases: enzymes in Aphanothece halophytica. 298 68

We previously reported that Brown Norway Katholiek rats, which feature a deficiency of plasma kininogens, develop severe abdominal aortic aneurysm. Increased activity of matrix metalloproteinases (MMPs) in the aortic wall, leading to degradation of extracellular matrix components, is considered to play a crucial role in aneurysm formation. Using an in vitro model of vascular smooth muscle cells (VSMCs), cultured from the rat aorta, we investigated whether the cleaved form of high molecular weight kininogen, designated HKa, affects the expression of MMP-9 and MMP-2 and their tissue inhibitors (TIMPs). Treatment of VSMCs with HKa reduced in a concentration-dependent manner IL-1alpha-induced release of MMP-9 and MMP-2, associated with decreased MMP enzymatic activity levels in conditioned media, as demonstrated by gelatin zymography and fluorescein-labeled gelatin substrate assay, respectively. Real-time PCR revealed that HKa reduced corresponding MMP-9 mRNA levels. Further investigations showed that this effect did not result from a modified rate of MMP-9 mRNA degradation. TIMP-1 mRNA levels, already increased as a result of cytokine-stimulation, were significantly enhanced by HKa. Furthermore, we found elevated basal mRNA expression levels of MMP-2 and TIMP-2 in VSMCs derived from kininogen-deficient Brown Norway Katholiek rats. These results demonstrate for the first time that HKa affects the regulation of MMPs in VSMCs.
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PMID:Cleaved high molecular weight kininogen, a novel factor in the regulation of matrix metalloproteinases in vascular smooth muscle cells. 1968 38