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T Tamura

Publications and source records attributed to T Tamura.

At least 1,441 records · Page 80Linked to original sources
PubMed1976

Purification to homogeneity and properties of two D-alanine carboxypeptidases I From Escherichia coli.

Three homogeneous preparations of D-alanine carboxypeptidases I have been obtained from Escherichia coli strain H2143, termed enzymes IA, IB, and IC. Enzyme IA purified from the membrane after extraction with Triton X-100 appeared on sodium dodecyl sulfate gel electrophoresis to be a polypeptide doublet whose monomer molecular weights were about 32,000 and 34,000. In addition to D-alanine carboxypeptidase activity, it catalyzed a transpeptidase reaction with several substrates, bound [14C]penicillin G, had a weak penicillinase activity, but was devoid of endopeptidase activity. Enzyme IB obtained from the membrane after LiCl extraction and enzyme IC obtained from the supernatant solution were either identical or extremely similar. They were composed of a single polypeptide whose monomer molecular weight was about 41,000. In addition to carboxypeptidase activity, they catalyzed an endopeptidase reaction, had weak penicillinase activity, and had very poor transpeptidase activity, but did not bind [14C]penicillin G. Some data relating to the mechanism of catalysis by these enzymes are described. Their possible physiological role is discussed.

Binding Sites↗
PubMed1976

Proton magnetic resonance spectra of tetracyclic triterpene alcohols under the influence of a lanthanide shift reagent.

The proton magnetic resonance spectra were measured for four series of tetracyclic triterpen-3beta-ols, i.e. 5alpha-lanostane, 5alpha-euphane, 5alpha-tirucallane, and 5alpha-dammarane series, in the presence of a molar equivalent of tris (dipivalomethanato) europium, a lanthanide shift reagent. The spectral pattern measured in the presence of the shift reagent was found useful for distinguishing each series and also for characterizing each skeletal isomer of tetracyclic triterpene alcohols.

Alcohols↗
PubMed1976

Zinc deficiency in two infants during total parenteral alimentation for diarrhea.

Zinc deficiency was observed in two infants receiving total parenteral alimentation for chronic diarrhea. An acrodermatitis enteropathica-like rash occurred in both of the infants. Staphylococcus aureus was cultured from the rash. Treatment with zinc resulted in rapid cure of the rash and a subsidence of other signs consistent with zinc deficiency.

Acrodermatitis↗
PubMed1976

The availability of folates in man: effect of orange juice supplement on intestinal conjugase.

The mechanisms of the low availability of endogenous folates in orange juice and the inhibitory effects on the availability of pteroylheptaglutamate (PteGlu7) caused by orange juice supplements were investigated in man by the use of simulated orange juice (containing the principal components: citric acid, malic acid, etc.) with several different pHs. The endogenous folates in orange juice were identified as mainly 5-methyl reduced derivatives of pteroylpolyglutamates (40-45% pentaglutamate, 10-15% tetraglutamate, 30-40% monoglutamate, and the rest were tri-and diglutamates). The availability of PteGlu7 is decreased to 54% by supplementation with 600 g concentrated orange juice (pH 3.7) and to 39% and 66% by the supplement of 24 g and 12 g citric acid (pH 3.7), respectively. Neutralization of 12 g citric acid to pH 6.4 largely reverses the inhibitory effect. On the other hand, the availability of pteroylmonoglutamate (PteGlu) is not influenced by a supplement of orange juice or citric acid. The results suggest that the low availability of PteGlu7 is due to the inhibition of intestinal conjugase caused by the low pH. These observations suggest that pH of foodstuffs may be an important factor in the absorption of polyglutamate forms of folate.

Adult↗
PubMed1976

Intracytoplasmic uncoated capsids of human cytomegalovirus.

It has been generally accepted that capsids found in the cytoplasm of infected fibroblasts by adapted strain human cytomegalovirus (CMV) have bristle-like surface coating on them. This coating was said to be one of the important differences of CMV from herpes simplex virus. As well known, capsids of CMV increased in their over-all diameter through the process of moving from the nucleus to the cytoplasm. In some instances, however, uncoated capsids were detected in the cytoplasmic portions especially in the vicinity of tubular structures in the cytoplasm. It seemed that these uncoated capsids might be formed in the cytoplasm but had not emigrated from the nucleus.

Capsid↗
PubMed1976

Serum zinc and copper levels in healthy Japanese children.

Serum zinc and copper concentrations of 156 healthy children (6-12 years old) were measured by the atomic absorption spectrophotometric method. The average serum zinc concentration was 92 +/- 13 mug/100 ml (mean +/- S.D.) with a range of 62-127 mug/100 ml. No statistically significant age or sex differences were found in serum zinc levels. The mean serum copper level was 109 +/- 17 mug/100 ml with a range of 70-164 mug/100 ml. Average serum copper concentration in younger age groups (6-9 years old) was higher than that in older age groups (10-12 years old). The highest value of mean serum copper level was observed in the group of 8-year-old children. No sex differences in serum copper levels were found in all the age groups.

Age Factors↗
PubMed1976

Studies of the cell envelope of Vibrio para-haemolyticus A55: isolation and purification of bag-shaped peptidoglycan (murein sacculus).

The peptidoglycan (PG) component of the envelope of Vibrio parahaemolyticus A55 was studied in relation to the salt dependency of the organism. A bag-shaped PG (murein sacculus) was isolated and purified by digestion of freshly harvested intact whole cells with sodium dodecyl sulfate (SDS) and then protease treatment. Whole cells lyze in salt-deficient or hypotonic conditions and this can be measured by turbidometry. Lysis is prevented by addition of 0.35 M NaCl or acidification to below pH 4.5. The isolated PG or murein sacculi did not seem to require salt for structural integrity. The PG obtained by the same method from subcellular fractions, that is, envelope fractions, prepared either with or without NaCl, was extensively fragmented. The main amino acids and amino sugars of the murein sacculus were glucosamine, muramic acid, alanine, glutamic acid, 2, 6-diamnopimelic acid (A2pm) in a molar ratio of 0.4:0.6:1.7:0.9:1.0. A polyglucose, which was only degraded by Pseudomonas isoamylase,and poly-beta-hydroxybutyrate (PHBA) were found in the murein sacculus. The murein sacculus of the organism is discussed in comparison with PG of other gram negative bacteria and marine or halophilic microorganisms.

Alanine↗