Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.27.1 (RNase)
 16,360 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The bovine exocrine pancreatic cell produces a variety of enzymes and proenzymes for export. Biochemical studies by Greene L.J., C.H. Hirs, and G.E. Palade (J. Biol. Chem. 1963. 238:2054) have shown that the mass proportions of several of these proteins in resting pancreatic juice and zymogen granule fractions are identical. In this study we have used immunocytochemical techniques at the electron microscope level to determine whether regional differences exist in the bovine gland with regard to production of individual secretory proteins and whether specialization of product handling occurs at the subcellular level. The technique used is a modification of one previously reported (McLean, J.D., and S.J. Singer. 1970. Proc. Natl. Acad. Sci U.S.A. 69:1771) in which immunocytochemical reagents are applied to thin sections of bovine serum albumin-imbedded tissue and zymogen granule fractions. A double antibody technique was used in which the first step consisted of rabbit F(ab')2 antibovine secretory protein and the detection step consisted of sheep (F(ab')2 antirabbit F(ab')2 conjugated to ferritin. The results showed that all exocrine cells in the gland, and all zymogen granules and Golgi cisternae in each cell, were qualitatively alike with regard to their content of secretory proteins examined (trypsinogen, chymotrypsinogen A, carboxypeptidase A, RNase, and DNase). The data suggest that these secretory proteins are transported through the cisternae of the Golgi complex where they are intermixed before copackaging in zymogen granules; passage through the Golgi complex is apparently obligatory for these (and likely all) secretory proteins, and is independent of extent of glycosylation, e.g., trypsinogen, a nonglycoprotein vs. DNase, a glycoprotein.
 ...
PMID:Immunocytochemical localization of secretory proteins in bovine pancreatic exocrine cells. 31

Changes in the activities of three gastric and nine pancreatic enzymes plus colipase were determined during postnatal development and weaning in calves. In calves exclusively milk-fed for 2, 7, 28, 56, 70 and 119 d, the enzyme activities per kilogram of empty live weight increased with age for chymotrypsin, elastase, carboxypeptidases A and B, ribonuclease and alpha-amylase, decreased for chymosin, lysozyme and colipase but showed no change in the case of pepsin, trypsin, lipase and phospholipase A2 compared with animals at birth. The greatest increase was that in alpha-amylase activity (about 50-fold between d 2 and 119). In calves weaned between d 28 and 56, all the activities were higher than in milk-fed animals, except that of chymosin (which was slightly lower) and that of colipase (which did not change). At 119 d of age, chymotrypsin, carboxypeptidase A, alpha-amylase and lipase were 1.6- to fourfold higher in ruminants than in preruminants. Thus, most enzyme activities were modified first by colostrum and milk intake, and again upon weaning by development of the forestomachs and ingestion of solid food. These ontogenic patterns might be under the control of many gut regulatory peptides, the plasma concentrations of which changed simultaneously. Some gastric and pancreatic enzymes were correlated to plasma concentrations of these gut regulatory peptides.
 ...
PMID:Gastric and pancreatic enzyme activities and their relationship with some gut regulatory peptides during postnatal development and weaning in calves. 137 46

The complete amino-acid sequence of BS-RNAse, a dimeric ribonuclease isolated from bovine seminal plasma, was determined. The reduced and S-carboxymethylated subunit chain of the enzyme was cleaved by trypsin and chymotrypsin. The resulting peptides, purified by cation-exchange chromatography were sequenced by dansyl-Edman, subtractive Edman degradation and carboxypeptidase A and B digestion. Chymotryptic peptides were used for the alignment. Automated Edman degradation of the native protein, through the N-terminal 41 amino-acid residues, completed the sequence information. The subunit chain of BS-RNAse, composed of 124 amino-acid residues, with a molecular mass of 13,610 Da, is highly homologous (81%) to pancreatic ribonuclease A. A good degree of homology (31%) was also found with human angiogenin. No N-linked carbohydrate-attachment sites, such as Asn-X-Ser/Thr, were found in the protein.
 ...
PMID:Complete amino-acid sequence of bovine seminal ribonuclease, a dimeric protein from seminal plasma. 342 1

The transplantable pancreatic acinar carcinomas of rat established recently provide useful model systems to examine the composition of secretory proteins as well as the secretory process in transformed pancreatic exocrine epithelium. The neoplastic acinar cells exhibit considerable variation in the extent of cytodifferentiation. In the present study the enzymatic profile of this heterogeneous tumor cell population has been investigated by the indirect immunofluorescent technique using antibodies against six pancreatic enzymes. By immunofluorescence, all neoplastic cells stained positively for the six enzymes tested: amylase, lipase, carboxypeptidase A, chymotrypsinogen, trypsinogen, and ribonuclease. Some variability in the intensity of immunofluorescence was noted, suggesting possible quantitative differences in the content of a given enzyme among tumor cells. These observations suggest that neoplastic acinar cells with or without secretory granules contain secretory proteins, but to a variable extent.
 ...
PMID:Immunohistochemical localization of pancreatic exocrine enzymes in normal and neoplastic pancreatic acinar epithelium of rat. 616 57

The pancreatic tissue of normal and virus-induced diabetic cattle was investigated by the indirect immunofluorescence technique. Seven secretory proteins (chymotrypsinogen A, trypsinogen, carboxypeptidase A, RNase, DNase, alpha-amylase and lipase) were localized in normal bovine pancreatic acinar cells but in diabetic animals amylase, lipase and carboxypeptidase were either not detectable or markedly diminished. Decrease in amylase content has been reported previously in other diabetic animals. The diminution of the three pancreatic enzymes may be related to the destruction of pancreatic endocrine tissue that occurs in these diabetic animals.
 ...
PMID:Alterations of exocrine pancreatic enzymes in virus-induced diabetic cattle as revealed by immunohistochemistry. 618 Sep 49

In order to investigate the role of carboxyl groups of a base non-specific ribonuclease from Aspergillus saitoi [EC 3.1.27.1] (RNase M, molecular weight 36,000), the modification of RNase M with a water-soluble carbodiimide, 1-cyclohexyl-3-(2-morpholinyl-(4)-ethyl)carbodiimide(CMC), was studied. The inactivation of RNase M proceeded almost linearly with the incorporation of about 9.5 CMC moieties. The peptide backbone structure of the modified RNase M was practically the same as that of the native RNase M, as assessed from the CD spectra in the region of 200-250 nm. In the presence of competitive inhibitors, adenosine, and cytidine, inactivation of RNase M by CMC was partially inhibited. In the presence of cytidine (1 M), the modification of about 4 carboxyl groups of RNase M proceeded with a slight loss of enzymatic activity (ca. 20%). Further modification inactivated RNase M with the incorporation of ca. 4-5 CMC without any detectable intramolecular peptide bond formation. Therefore, it was concluded that carboxyl groups responsible for enzymatic activity were included among these carboxyl groups protected by cytidine. The logarithm of the half-live of the inactivation of RNase M by CMC was a linear function of log[CMC] with a slope of minus one, indicating that at least one carboxyl group among the modified ones may be essential for catalysis. The digestion of CMC-modified RNase M with carboxypeptidase A eliminated the carboxyl terminal group from the site of CMC modification.
 ...
PMID:Modification of a major ribonuclease from Aspergillus saitoi with 1-cyclohexyl-3-(2-morpholinyl-(4)-ethyl)carbodiimide. 657 11

A bifidogenic growth stimulator was present in the cell-free filtrate of Propionibacterium freudenreichii 7025 culture and in the methanol extract fraction of the cells. Several intestinal bacteria, such as Bacteroides, Enterobacter, and Enterococcus, which also released a growth stimulator for bifidobacteria, may play an important role in regulation of a bifidobacterial population in colonic microflora. The water-soluble stimulator from the methanol extract of the cells was partially purified. The molecular weight of the stimulator appeared to be < 3000. The stimulatory activity was unaffected by treatments with pronase, carboxypeptidase A, ribonuclease, or nuclease P1 and was heat stable over a wide pH range. This stimulator differed from cyanocobalamin and from organic acids, such as acetate and propionate. Because it was stable to heat and proteolytic enzymes, the stimulator is a useful bifidogenic factor that can reach the large intestine while retaining its activity. Short-chain fatty acids were highly inhibitory to the growth of many intestinal bacteria, particularly Gram-negative facultative and obligatory anaerobes. The short-chain fatty acids (especially propionate) stimulated the growth of bifidobacteria. The growth of Bifidobacterium adolescentis 6003 was further enhanced in the presence of short-chain fatty acids and the stimulator produced by P. freudenreichii 7025. Viable counts of strain 6003 grown with Bacteroides vulgatus JCM 5826T increased more than 10(4) over those of the single culture of strain 6003. However, the growth of strain 6003 was inhibited in the mixed culture with Clostridium perfringens 7028. In continuous culture, the growth of bifidobacterial strain 6003 could be greatly enhanced, even in the presence of clostridial strain 7028, in media with short-chain fatty acids and stimulator produced by P. freudenreichii 7025.
 ...
PMID:Growth stimulator for bifidobacteria produced by Propionibacterium freudenreichii and several intestinal bacteria. 818 63