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M Kitamikado

Publications and source records attributed to M Kitamikado.

12 recordsLinked to original sources
PubMed1992

Two types of bacterial alginate lyases.

The extracellular alginate lyases were purified from Vibrio harveyi AL-128 and V. alginolyticus ATCC 17749. The former enzyme appears to be specific for alpha-1,4 bonds involving L-guluronate units in alginate, whereas the latter exhibits specificity for beta-1,4 bonds involving D-mannuronate units. The molecular weights of the enzymes were estimated to be 57,000 and 47,000, and they had isoelectric points of 4.3 and 4.6, respectively. The enzyme from strain AL-128 was most active at NaCl concentrations of 0.3 to 1.0 M. Optimum activity of the enzyme from strain ATCC 17749 was found in the presence of 5 to 10 mM CaCl2.

Alginates↗
PubMed1990

Purification and characterization of a novel beta-agarase from Vibrio sp. AP-2.

beta-Agarase was purified from the culture fluid of a porphyran-decomposing marine bacterium (strain AP-2) by ammonium sulfate precipitation, successive column chromatography and DNase and RNase treatment. The final enzyme preparation appeared to be homogeneous on polyacrylamide gel electrophoresis. The enzyme had a molecular mass of 20 kDa, a pH optimum of 5.5, and was stable in the pH region 4.0-9.0 and at temperatures below 45 degrees C. The beta-agarase was a novel endo-type enzyme which hydrolyzed neoagarotetraose, larger neoagarooligosaccharides and agar to give neoagarobiose [3,6-anhydro-alpha-L-galactopyranosyl-(1----3)-D-galactose] as the predominant product. The enzyme did not act on kappa-carrageenan. According to the criteria of Bergey's Manual of Systematic Bacteriology, the strain was assigned to the genus Vibrio.

Chromatography↗
PubMed1990

Method designed to detect alginate-degrading bacteria.

A simple turbidimetric method was developed to detect alginate degradation. Bacteria were grown in alginate-containing media, and culture fluids were mixed with an acidic albumin solution. Failure to develop a white turbidity indicated an alginate degrader. The method showed alginate degradation by Vibrio alginolyticus ATCC 17749, in contrast to prior descriptions.

Journal Article↗
PubMed1984

Isolation and characterization of an asparagine-linked keratan sulfate from the skin of a marine teleost, Scomber japonicus.

Keratan sulfate was isolated from the skin of Pacific mackerel (Scomber japonicus) after exhaustive digestion with pronase followed by ethanol precipitation and fractionation on a cellulose column with 0.3% recovery of dried material. The keratan sulfate preparation was separated into four major fractions by Dowex-1 column chromatography. The chemical and infrared spectrum analyses of the four fractions showed a high degree of heterogeneity in sulfation. Since the carbohydrate-peptide linkage in the teleost skin keratan sulfate was found to be stable in alkali, and asparagine was the predominant amino acid, the asparagine residue in the peptide backbone was most likely to be involved in the N-glycosyl linkage with the carbohydrate moiety. Besides the type of carbohydrate-peptide linkage, the teleost skin keratan sulfate is very similar to corneal keratan sulfate (keratan sulfate I) in two respects: (1) The teleost skin and bovine corneal keratan sulfates were hydrolyzed much faster by endo-beta-galactosidase than the whale nasal cartilage keratan sulfate (keratan sulfate II). (2) Although the teleost skin keratan sulfate showed considerable polydispersity, the molecular weight was in the same range as the corneal keratan sulfate, and it was relatively higher than that of the cartilage keratan sulfate.

Amino Acids↗
PubMed1983

The use of mannan-Sepharose 4B affinity chromatography for the purification of endo-beta-N-acetylglucosaminidase from Bacillus alvei.

In order to facilitate the isolation of endo-beta-N-acetylglucosaminidase for the structural analysis of glycoconjugates, we have isolated a strain of Bacillus alvei which produces a high level of endo-beta-N-acetylglucosaminidase. We have also devised a simple procedure for the purification of endo-beta-N-acetylglucosaminidase from B. alvei using mannan-Sepharose affinity chromatography. By using this method, endo-beta-N-acetylglucosaminidase was purified 3300-fold with 85% yield from the crude enzyme obtained by ammonium sulfate precipitation of the culture medium. The molecular weight of this enzyme was estimated to be about 66 000 by gel filtration. When using (Man)6(GlcNAc)2-Asn-Dns as substrate, the optimal activity occurs at pH 6.5 with Km of 1.9 mM. The action of endo-beta-N-acetylglucosaminidase toward several glycopeptides was also studied.

Acetylglucosaminidase↗
PubMed1982

Purification and characterization of a novel exo-beta-mannanase from Aeromonas sp. F-25.

A novel exo-beta-mannanase (1,4-beta-D-mannan mannobiohydrolase) was isolated from the culture fluid of strain No. F-25 of Aeromonas hydrophila subspecies anaerogenes, and purified about 4,000-fold by ammonium sulfate precipitation and successive co.umn chromatographies. The final enzyme preparation appeared to be homogeneous on polyacrylamide gel electrophoresis. The enzyme hydrolyzed the beta-1,4-mannan link in polysaccharides of three or more beta-1,4-linked D-mannose units. The enzyme had a molecular weight of 64,000, pI of 5.9, pH optimum of 6.0, and was stable in a pH region of 5.0 to 8.5 and at temperatures below 45 degrees C. The Km values of the enzyme were 5.1 X 10(-4) M for mannotriose, 2.4 X 10(-4) M for mannotetraose and 1.3 X 10(-4) M for mannopentaose. The enzyme attacked codium and coffee mannans to give only mannobiose. Mannobiosyl- and mannotetraosyl-mannitol were hydrolyzed to produce mannobiose and mannitol, while mannobiose and mannosylmannitol were released from mannotriosylmannitol. The enzyme did not act on mannobiose, p-nitrophenyl-beta-D-mannoside, konjac glucomannan, or guar gum galactomannan. Furthermore, the enzyme catalyzed a transglycosylation reaction.

Aeromonas↗
PubMed1980

Isolation and characterization of an endo-beta-galactosidase from a new strain of Escherichia freundii.

A new strain of Escherichia freundii was isolated from human feces. Compared with the previous strain (Kitamikado, M., and Ueno, R. (1970) Bull. Jpn. Soc. Sci. Fish. 36, 1175-1180), this strain releases comparable levels of endo-beta-galactosidase with lower levels of exoglycosidases in the culture medium containing 0.3% of keratan sulfate. Endo-beta-galactosidase was purified by an improved purification procedure involving Amicon H1P10 hollow fiber filtration, QAE-Sephadex A-50, and CM-Sephadex C-50 chromatographies. The purified enzyme is completely free from proteases and exoglycosidases. The general properties of this enzyme are: molecular weight, 28,000; optimal pH, 5.5 TO 5.8; PI, pH 8.0. This enzyme hydrolyzed keratan sulfates isolated from different sources to produce 6-O-sulfo-GlcNAc beta1 leads to 3Gal as the major product. In addition, the specificity of this enzyme toward various glycoconjugates was also studied.

Animals↗
PubMed1975

Chondroitinase-producing bacteria in natural habitats.

A search was undertaken for bacteria which degrade chondroitin sulfate in nature and to find bacteria with a usefully high rate of chondroitinase (ChSase) productivity. First, 253 ChSase-producing bacteria were obtained from aquatic and land environments in Japan by aerobic and anaerobic screening methods. Identification according to Bergey's Manual of Determinative Bacteriology or Bain and Shewan (1968) permitted assignment of the majority of the isolates to seven genera, Aeromonas, Vibrio, Flavobacterium, Beneckea, Proteus, Micrococcus, and Arthrobacter. Next, ChSase productivities of all the isolates were compared with those of two established ChSase-producing stock strains, Proteus vulgaris NCTC 4636 and Flavobacterium heparinum ATCC 13125. As a result, special attention was given to production by a strain of Aeromonas sp. of large quantities of extracellular ChSase-AC. None of the isolates from the current study displayed significant ChSase-ABC productivity. Finally, ChSase-AC was prepared from the culture fluid of the Aeromonas strain by fractional precipitation with ammonium sulfate, chromatography on phospho-cellulose and diethylaminoethyl-cellulose, and gel filtration on Sephadex G-200. It was concluded that the Aeromonas strain may represent a profitable source of the enzyme ChSase-AC.

Aerobiosis↗