Stomach bovine

Calf stomach (bovine, camel), recombinant E. coli, yeast, and filamentous fungi... 

Some work has been completed on reaction of proteins with nitrite followed by hydrolysis and analysis for amino acids It has been shown that 3-nitrotyrosine and 3,4-dihydroxyphenylalanine are formed from bovine serum albumin when nitrosation occurs under conditions similar to those found in the human stomach (36), Direct demonstration that nitrite reacts with protein has been made by using NaN02 with bovine serum albumin (pH 5.5, 20 C and 200 ppm nitrite). A 60% loss of the originally added nitrite was observed in one week and nearly half of the nitrite (labelled %) could be recovered from the protein. Similar work with myosin revealed that 10-20% of the incorporated label was present as 3-nitrotyro-sine (J7). 

Walsh, M.P. Hinkins, S. Flink, I.L. Hartshorne, D.J. Bovine stomach myosin light chain kinase purification, characterization, and comparison with the turkey gizzard enzyme. Biochemistry, 21, 6890-6896 (1982)... 

Linklater (1961) reported that bovine pepsin accounted for only 0 to 6% of the milk-clotting activity of commercial rennet extracts. He used porcine pepsin as a reference standard. Bovine pepsin has increased in use as a coagulant because of the practice of extracting the stomach from older calves and adult cattle. More recently, Sellers (1982) reported that 85 to 95% of the proteolytic activity of calf rennet is due to chymosin and the remainder is from bovine pepsin. Adult bovine rennets preparations may contain 55 to 60% bovine pepsin. Mixtures of calf rennet and porcine pepsin may contain 40 to 45% chymosin, 5 to 10% bovine pepsin, and 50% porcine pepsin. Mixtures of adult bovine rennet and porcine pepsin typically contain 20 to 25% chymosin, 40 to 45% bovine pepsin, and 30 to 40% porcine pepsin activity (McMahon and Brown 1985). 

XII. Preparation of Blood Group Substances from Bovine Stomach Linings and a Comparison of Their Chemical and Immunochemical Properties with Those of Blood Group Substances from Other Species/ J. Immunol. (1952) 68,19. 

Recently, Wada et al. (1999) have demonstrated that a daily oral dose of 10 mg of bovine LF for 3-4 weeks to H. pylori-infected mice significantly decreased the number of this bacterium colonising in the stomach. The authors suggested that the glycans present in LF may bind to the bacterial adhesins, thus interfering with the attachment of H. pylori to the epithelial cells. These findings are supported by another mouse model study (Dial et al., 1998), which showed that oral administration of 4 mg of bovine LF per day for 3 weeks reduces gastric urease activity and H. pylori colonisation in the stomach. 

SHIME Stomach Small intestine Stomach Gastric juice (pepsin, mucin, BSA), pH 1.1 Intestinal juice (bovine bile, pancreatine, lipase, BSA), pH 8.0 SHIME medium (pectin, Pb As, Cd, 5, 13... 

Today, active bovine chymosin has been successfully produced from several filamentous fungi and they are indistinguishable from the natural enzyme obtained from calves stomachs. 

Rennet, Bovine Aqueous extracts made from the fourth stomach of bo vines. Produced as a clear, amber to dark brown liquid or a white to tan powder. Major active principle protease (pepsin). Typical application used in the manufacture of... 

Amino acid residue Human milk, leukemic urine Baboon milk Horse milk Rat urine Bovine stomach mucosa C2 Deer stomach mucosa Langur stomach mucosa Pig Stomach mucosa 3 Echidna milk I Rabbit spleen Canine spleen Grey kan- garoo... 

Langur stomach mucosa (LS Iz) (6) Bovine stomach Iz 1,3 Ovine stomach Iz 1,2,3 ... 

Jolles et al. (1984) determined the 129-residue sequence of one of the three variants (variant 2) of the three c-type lysozymes isolated by Dobson et al. (1984) from bovine stomach mucosa. The sequence is given here. However, residue 98 has been altered from the original designa-don of Lys to His in accordance with the revision by R Jolles and J. Jolles (quoted by Prager and Wilson, 1988). Note (6) Work by Jolles et al. (1990) on the other bovine variants and two variants of caprine stomach mucosa lysozyme, and by Irwin and Wilson (1990) on three ovine variants, was in press at the time of writing and the following information was made available courtesy of Ellen Prager and Allan Wilson. 

Bovine stomach mucosal lysozyme Ci and Cs differ from c as follows ... 

The chain lengths of all but three of the a-lactalbumins, considered in Section B, are 123 residues. One, rat a-lactalbumin, has a chain extension of 17 residues, giving 140 residues total. In their nucleotide sequence study Qasba and Safaya (1984) concluded that this extension arises from a T-to-G base change in the termination codon. Two sequences have fewer than 123 residues Rabbit has 122 residues and red-necked wallaby has 121 residues. The majority of the mammalian lysozymes (human, baboon, and equine milk rat urine and camel, pig 3, and langur stomach) have 130 residues. Bovine, caprine, and deer stomach lysozymes have 129 residues. Although pig stomach lysozyme 3 has 130 residues, two of its variants (1 and 2) have 128... 

If domestic hen egg-white lysozyme (Jung et al., 1980), human lysozyme (Peters et al., 1989), and bovine stomach (Irwin et al., 1989) are included in the comparison, introns occur at positions in the genes for the two lysozymes corresponding to those for the four a-lactalbumins (Acharya et al., 1989, comment that such results do not appear to agree... 

In Section VII,B and Fig. 10 we compared the sequences of 13 a-lactalbumins (if the bovine A variant, equine B and C variants, and ovine variant are included), 23 mammalian c-type lysozymes (if donkey, mouse M, bovine stomach 1 and 3, caprine 1 and 2, ovine 1-3, camel 1, deer 2, echidna II, and porcine 1 and 2 are included), and 13 avian c-type lysozymes (if KDIII and PD2 and PD3 are included). Analysis of the sequence differences indicates that, with the recent considerable increase in the number of lysozymes sequenced, there has been an appreciable decrease in the numbers of residues that are invariant in lysozymes as well as for both proteins. Nevertheless, there is still significant overall homology (—35%) between a-lactalbumin and c-type lysozyme. From the similarities in amino acid sequences, three-dimensional structures, intron—exon patterns, etc., there can be little doubt that the concept of divergence is still valid for these proteins. What is controversial are the rate of evolution and the details of the way in which ct-lactalbumin arose, although it is conceded generally that the mechanism involves gene duplication. 

A brilliant success of modern biochemistry has been to show that all or almost all proteins of bovine pancreatic juice are enzymes (1). It may be said in a cursory way that this juice is a solution of enzymes in bicarbonate and that its composition is strictly utilitarian. Bicarbonate is present in order to neutralize hydrochloric acid coming from the stomach and to keep enzymes in solution. Enzymes are present for digesting alimentary products in the intestine. On the other hand, pancreatic juice seems to have been created for the protein chemist s delight, since its proteins are biologically active, relatively simple, and endowed with unusual properties. 

Les.), and Couceiro, de Almeida, and Freire (1953) have localized it histo-chemically in the electrical tissue of Electwphorus electricus L. The distribution of carbonic anhydrase in several tissues of two teleosts and its inhibition in vivo by the sulfonamides have been investigated by Maetz (1953a,b). The presence of cathepsin in the stomachs of various animals including pike and trout has been established by Buchs (1954). A new advance has also been made in the comparative study of pepsin. This enzyme, previously crystallized from salmon (Norris and Elam, 1940), halibut (Eriksen, 1943), and shark (Sprissler, 1942), has now been crystallized from three species of tuna (Norris and Mathies, 1953). These interesting researches have shown that fish pepsins differ in crystal structure, amino acid composition, and specificity from swine or bovine pepsins and show a closer relationship to one another. As pointed out by Velick and Udenfriend (1953), specificity requirements toward substrates are less exacting with extracellular enzymes. 

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