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21.
Primary structure of β-chain of pigeon is presented. It was determined by amino acid sequence analysis of intact β-chain and its peptides obtained by the enzymatic and chemical cleavage. Comparison of amino acid sequence of the chain with other available data shows β 14 Ile, β61 Lys, and β113 Ile as residues specific to pigeon. One important replacement at α1β1 contact is β55 Met→Ser. 相似文献
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We have earlier identified and purified two protein-lysine N-methyltransferases (Protein methylase III) fromEuglena gracilis [J. Biol. Chem.,260, 7114 (1985)]. The enzymes were highly specific toward histone H1 (lysine-rich), and the enzymatic products were identified as ε-N-mono-, di- and trimethyllysines. These earlier studies, however, were carried out with rat liver histone H1 as thein vitro substrate. Presently, histone H1 has been purified fromEuglena gracilis through Bio-Rex 70 and Bio-Gel P-100 column chromatography. TheEuglena histone H1 showed a single band on SDS-polyacrylamide gel electrophoresis and behaved like other histone H1 of higher animals, whereas it had a much higherR f value than the other histones H1 in acid/urea gel electrophoresis. When theEuglena histone H1 was [methyl-3H]-labeledin vitro by a homologous enzyme (one of the twoEuglena protein methylase III) and analyzed on two-dimensional gel electrophoresis, three distinctive subtypes of histone H1 were shown to be radiolabeled, whereas five subtypes of rat liver histone H1 were found to be labeled. Finally, by the combined use of a strong cation exchange and reversed-phase Resolve C18 columns on HPLC, we demonstrated thatEuglena histone H1 contains approximately 9 mol% of ε-N-methyllysines (1.40, 1.66, and 5.62 mol% for ε-N-mono-, di- and trimethyllysines, respectively). This is the first demonstration of the natural occurrence of ε-N-methyllysines in histone H1. 相似文献
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Copper metabolism in a teleost, the plaice, Pleuronectes platessa (L.) from a natural environment has been studied. Distribution in the various tissues of the metal and of five key copper-dependent enzymes: ceruloplasmin EC 1.16.3.1; Superoxide dismutase EC 1.15.11; tryptophan oxygenase EC 1.13.1.12; cytochrome oxidase EC 1.9.3.1 and monoamine oxidase EC 1.4.3.4 have been determined. The copper distribution was found to be similar to that in mammals with the greatest concentrations in the brain and heart. Distribution of the copper enzymes is also similar to that found in mammals. A preliminary characterization of the copper enzymes showed that plaice cytochrome oxidase has a pH maximum 2 pH units more alkaline than the mammalian enzyme and that plaice tryptophan oxygenase is more sensitive to heat denaturation than the mammalian enzyme. The present data form a base-line against which studies on factors affecting the copper metabolism in a teleost can be assessed. 相似文献
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The role of chlorinated primary effluents in viral pollution of the Ottawa River (Ontario) was assessed by examining 282 field samples of wastewaters from two different sewage treatment plants over a 2-year period. The talc-Celite technique was used for sample concentration, and BS-C-1 cells were employed for virus detection. Viruses were detected in 80% (75/94) of raw sewage, 72% (68/94) of primary effluent, and 56% (53/94) of chlorinated effluent samples. Both raw sewage and primary effluent samples contained about 100 viral infective units (VIU) per 100 ml. Chlorination produced a 10- to 50-fold reduction in VIU and gave nearly 2.7 VIU/100 ml of chlorinated primary effluent. With a combined daily chlorinated primary effluent output of approximately 3.7 × 108 liters, these two plants were discharging 1.0 × 1010 VIU per day. Because the river has a mean annual flow of 8.0 × 1010 liters per day, these two sources alone produced a virus loading of 1.0 VIU/8 liters of the river water. This river also receives at least 9.0 × 107 liters of raw sewage per day and undetermined but substantial amounts of storm waters and agricultural wastes. It is used for recreation and acts as a source of potable water for some 6.0 × 105 people. In view of the potential of water for disease transmission, discharge of such wastes into the water environment needs to be minimized. 相似文献
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Syed Siraj-ul-Islam Chintala V.N. Rao Atindra N. Chakraborty S. Ghosh Dastidar 《Carbohydrate research》1982,110(1):69-75
The lipopolysaccharide isolated from the cells of Shigella boydii type 8 bacteria gave precipitin bands against homologous antisera on Ouchterlony plates, whereas the carbohydrate-containing fractions obtained from it did not. One of the fractions was obtained in major proportion and contained 23.5% of sugars. A structure was assigned to the carbohydrate chain in this material by using the results of methylation, periodate oxidation, and deamination studies. 相似文献