Faculty Profiles - KANZAKI Hiroshi

MISC - KANZAKI Hiroshi

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Effective production of dehydro cyclic dipeptide albonoursin exhibiting pronuclear fusion inhibitory activity. I. Taxonomy and fermentation

Hiroshi Kanzaki, Daisuke Imura, Reiko Sashida, Akio Kobayashi, Kazuyoshi Kawazu

Journal of Antibiotics 52 ( 11 ) 1017 - 1022 1999

Language：English Publisher：Japan Antibiotics Research Association

Strain KO-23, an actinomycete producing albonoursin as well as streptopyrone, was identified as Streptomyces albulus by morphological and biochemical studies. Fermentation conditions for albonoursin, a dehydro cyclic dipeptide exhibiting a pronounced inhibitory activity toward pronuclear fusion of sea urchin eggs, were optimized. Under the optimum conditions, the actinomycete produced 16 mg/liter of albonoursin, 30 times higher than that in the original culture. The cells cultivated under these conditions highly express biosynthetic enzymes for albonoursin, and thus are available for biosynthetic studies of dehydro cyclic peptides.

DOI： 10.7164/antibiotics.52.1017

病原体を接種して萎凋させたアカマツ実生からの病原体の再分離およびマツノザイセンチュウの分離系統間の病原性の差異．

河津一儀, 金子昇, 平岡享子, 山下秀昭, 神崎浩

岡山大学農学部学術報告 88 1 - 6 1999

新規の環状ジペプチド脱水素酵素とその活性測定法の確立．

神崎浩, 赤澤和美, 井村大輔, 仁戸田照彦

岡山大学農学部学術報告 1999

Microbial hyrodolysis of cyclo(Gly-Leu)

Kanzaki Hiroshi, Mizuta Naoki, Miyoshi Kazuyuki, Nitoda Teruhiko

11 202 - 202 1999

Calophyllum inophyllumの抗HIV活性成分inophyllum A,B,C,D,E,Pの液体クロマトグラフィー・による分析法の確立

河津一儀, 仁戸田照彦, 神崎浩

岡山大学農学部学術報告 87 13 - 16 1998.2

Novel bioactive oxazolomycin isomers produced by streptomyces albus JA3453

Hiroshi Kanzaki, Ken-Ichi Wada, Teruhiko Nitoda, Kazuyoshi Kawazu

Bioscience, Biotechnology and Biochemistry 62 ( 3 ) 438 - 442 1998

Language：English

Two novel oxazolomycin isomers, oxazolomycins B (2) and C (3), were isolated from the fermentation broth of an oxazolomycin-producing strain, Streptomyces albus JA3453. Both compounds are geometrical isomers of oxazolomycin (1), the configurations of their triene moieties being (4′E, 6′E, 8′E) (2) and (4′Z, 6′E, 8′E) (3) while that of oxazolomycin (1) is (4′Z, 6′Z, 8′E). Compounds 2 and 3 exhibited potent inhibitory activity against crown gall formation with the same MIC (0.8 μg/disk) as oxazolomycin. Compounds 2 and 3 showed no antibacterial activity against Agrobacterium tumefaciens, in contrast to oxazolomycin which has specific anti-A. tumefaciens activity. © 1998, Taylor &amp
Francis Group, LLC. All rights reserved.

DOI： 10.1271/bbb.62.438

Improved bioassay method for plant transformation inhibitors

Hiroshi Kanzaki, Toshihiko Kagemori, Satomi Asano, Kazuyoshi Kawazu

Bioscience, Biotechnology and Biochemistry 62 ( 12 ) 2328 - 2333 1998

Language：English

A convenient and quantitative bioassay method for evaluating the efficiency of plant transformation by Agrobacterium tumefaciens is important to search plant transformation inhibitors, possible biochemical probes for study on its mechanism. Our previously reported method, in which the plant transformation had been detected by the expression of β-glucuronidase in transformed plants, was improved. The difference between the previous and the improved methods is the use of suspension-cultured cells of Ageratum conyzoides as the host plant instead of Nicotiana tabacum BY-2
this alteration of the host enabled us to measure the β-glucuronidase activity in plant cells not only fluorometrically but also colorimetrically. The enzyme activity expressed in the cells of A. conyzoides was nearly 100 times higher than that of N. tabacum BY-2, and was enough for detection by colorimetric measurement. The method, therefore, is useful for a convenient determination of inhibitory activity against plant transformation. © 1998, Taylor &amp
Francis Group, LLC. All rights reserved.

DOI： 10.1271/bbb.62.2328

Microbial hydrolysis of diketopiperazines: Different types of diketopiperazine-assimilating bacteria

H Kanzaki, S Oda, A Kobayashi, K Kawazu

JOURNAL OF FERMENTATION AND BIOENGINEERING 83 ( 4 ) 386 - 388 1997

Language：English Publisher：SOC FERMENTATION BIOENGINEERING, JAPAN

Arthrobacter sp. 1-3-1 and a coryneform rod bacterium, strain T-1-3-Y, which assimilate cyclo(Gly-Gly) and cyclo(Gly-L-Tyr) at high rates, respectively, were isolated from sell. Both bacteria exhibit diketopiperazine-hydrolyzing activity intracellularly in contrast to the extracellular cyclo(Gly-Gly) hydrolase reported previously. Arthrobacter sp. 1-3-1 shows a much broader substrate specificity than strain T-1-3-Y, indicating the diversity of diketopiperazine hydrolysis in nature.

DOI： 10.1016/S0922-338X(97)80147-X

Inhibitory effect of curromycins and their esters on plant transformation

Hiroshi Kanzaki, Toshitsune Ichioka, Akio Kobayashi, Kazuyoshi Kawazu

Bioscience, Biotechnology and Biochemistry 60 ( 9 ) 1535 - 1537 1996

Language：English

Curromycins A and B, antibiotics specific to Agrobacterium tumefaciens, inhibited crown gall formation on potato tubers. Their esters showed potent inhibitory activity against crown gall formation without any antibacterial activity. The change in biological activity of curromycins by simple esterification was similar to our previous observation in oxazolomycin. Curromycin esters are possible chemical probes to study the mechanism for plant transformation. © 1996, Taylor &amp
Francis Group, LLC. All rights reserved.

DOI： 10.1271/bbb.60.1535

An effective method of screening glucose-rich microbial culture filtrates for insect trehalase inhibitors

Hiroshi Kanzaki, Takafumi Nuhama, Akio Kobayashi, Kazuyoshi Kawazu

Bioscience, Biotechnology and Biochemistry 59 ( 3 ) 398 - 400 1995

Language：English

Trehalase inhibitors are promising as a specific insect growth regulator. Microbial culture filtrates are a good source of bioactive compounds, but some of them retain a significant amount of glucose, a major component of the culture medium, which makes it difficult to detect trehalase inhibitors because of high blank values for the glucose determination. To find a variety of trehalase inhibitors in glucose-rich microbial culture filtrates, an effective method for removing glucose by enzymatic conversion prior to a routine trehalase-inhibitory assay was devised. Conversion with glucose oxidase and catalase could completely remove 10mg/ml of glucose, and a wide variety of microbial culture filtrates with high glucose content could then be subjected to the routine bioassay. This method can also be applied to screen inhibitors for other enzymes whose activity is assayed by the amount of glucose formed. © 1995 Taylor &amp
Francis Group LLC.

DOI： 10.1080/bbb.59.398

A novel bioassay method for inhibitors against plant transformation

Kanzaki Hiroshi, Toyoshima Hiroto, Kobayashi Akio, Kawazu Kazuyoshi

Bioscience, Biotechnology and Biochemistry 58 ( 3 ) 531 - 534 1994.3

Language：English Publisher：Japan Society for Bioscience, Biotechnology, and Agrochemistry

A rapid and quantitative bioassay method for inhibitors of plant transformation by Agrobacterium tumefaciens with an intron-GUS binary vector was devised as an alternative method to the time-consuming potato tuber disk assay. Among several host plants tested, tobacco BY-2 suspension cells were the most preferable for this GUS expression assay. Furthermore, as the phytotoxicity of the test material, if any, is apparent from the growth inhibition of BY-2 suspension cells, this method can exclude phytotoxic com pounds.

DOI： 10.1271/bbb.58.531

A Novel Bioassay Method for Inhibitors of Plant Transformation

Kanzaki Hiroshi, Toyoshima Hiroto, Kobayashi Akio, Kawazu Kazuyoshi

Bioscience, biotechnology, and biochemistry 58 ( 3 ) 531 - 534 1994.3

Language：English Publisher：Japan Society for Bioscience, Biotechnology, and Agrochemistry

A rapid and quantitative bioassay method for inhibitors of plant transformation by Agrobacterium tumefaciens with an intron-GUS binary vector was devised as an alternative method to the time-consuming potato tuber disk assay. Among several host plants tested, tobacco BY-2 suspension cells were the most preferable for this GUS expression assay. Furthermore, as the phytotoxicity of the test material, if any, is apparent from the growth inhibition of BY-2 suspension cells, this method can exclude phytotoxic com pounds.

DOI： 10.1271/bbb.58.531

47 THE ROLE OF PEROXIDASE IN THE CHEMICAL DEFENCE OF PLANTS : A NOVEL PEROXIDASE INHIBITOR AND A NEW TYPE OF BIOACTIVE PHENOLICS PRODUCED BY PEROXIDASE

Kobayashi A, Koguchi Y, Kanzaki H, Kajiyama S, Kawazu K

天然有機化合物討論会講演要旨集 ( 35 ) 361 - 368 1993.9

Language：Japanese Publisher：天然有機化合物討論会

Plants induce varied resistance-response toward microbial challenge. In order to establish an infection, pathogenic fungi must break such defense barriers as lignin, phytoalexins, and hydrolytic enzymes. At the early stage of infection, POD (peroxidase) activity is enhanced dramatically. POD and lignin accumulates at the infected site and then protects from further fungal invasion. The suppression of lignin deposition at the site might be of advantage to susceptible pathogenic fungi. We, therefore, conducted a comprehensive screening to obtain POD inhibitors from fungal cultures and a potent radical scavenger named ST-1 was isolated from a fungus, and its chemical structure was elucidated to be 1,3-dihydro-4,5,6-trihydroxy-1,3-dimethoxy-7-methylisobenzofuran by a combination of chemical modification and spectroscopic techniques. ST-1 effectively scavenged oxygen radicals and also suppressed the phytoalexin accumulation in kidney bean. These results suggested that such a mechanism can be enumerated as one of significant defense systems intervening plants and microbes. On the other hand, the POD, activated upon pathogenic challenge, could convert common plant phenolics into bioactive compounds which interfered with pathogen and insect attacks. This idea prompted us to examine the possibility. Guaiacol and other phenols were chosen as model substrates for the enzyme reaction system, and several products with novel structures were confirmed to have unique biological activities. This paper deals with the chemical structures of a novel radical scavenger (ST-1) and the POD products with anti-microbial activities and phytotoxicities.

DOI： 10.24496/tennenyuki.35.0_361

Bisanthraquinones, Inhibitors of Plant Transformation

Hiroshi Kanzaki, Goro Kawabata, Akio Kobayashi, Kazuyoshi Kawazu

Bioscience, Biotechnology, and Biochemistry 57 ( 12 ) 2104 - 2106 1993

Language：English

A potato tuber disk assay of culture broths which had been confirmed to show neither antibacterial nor phytotoxic activity resulted in the discovery of a novel type of crown gall formation inhibitors, julimycin B-II and julichrome Q1.3. These two bisanthraquinones, products of Streptomyces sp. TM-71, inhibited crown gall formation on potato tuber disks at a minimum inhibitory dose of 1.6μg/disk without affecting the growth of Agrobacterium tumefaciens or the germination of alfalfa seeds. © 1993, Japan Society for Bioscience, Biotechnology, and Agrochemistry. All rights reserved.

DOI： 10.1271/bbb.57.2104

Oxazolomycin Esters, Specific Inhibitors of Plant Transformation

Kazuyoshi Kawazu, Goro Kawabata, Satoru Kawai, Akio Kobayashi, Hiroshi Kanzaki

Bioscience, Biotechnology and Biochemistry 56 ( 9 ) 1382 - 1385 1992

Language：English

Oxazolomycin diacetate, dipropionate, monobutyrate and dibutyrate were derived from oxazolomycin, a product of Streptomyces sp. KBFP-2025. These esters were potent inhibitors of crown gall formation on potato tuber disks upon infection with Agrobacterium tumefaciens. They showed neither antibacterial nor phytotoxic activity, whereas oxazolomycin showed both antibacterial and phytotoxic activities. Further, they had no inhibitory activity against A. tumefaciens on the potato tuber disk. The inhibitory activity of these esters against crown gall formation seems to be due to specific inhibition of the transformation of plants with A. tumefaciens. © 1992, Japan Society for Bioscience, Biotechnology, and Agrochemistry. All rights reserved.

DOI： 10.1271/bbb.56.1382

Preparation and identification of the alfalfa elicitor from brown algae laminaran.

KOBAYASHI Akio, TAI Akihiro, KANZAKI Hiroshi, KAWAZU Kazuyoshi

Chemical Regulation of Plants 26 ( 2 ) 222 - 222 1991.12

Production of Benzoylformic Acid from Phenylglycine by Saccharomycopsis lipolytica

Hiroshi Kanzaki, Atsuhiko Isobe, Yoshikazu Izumi, Hideaki Yamada

Agricultural and Biological Chemistry 54 ( 8 ) 2101 - 2105 1990

Language：English

Microbial production of benzoylformic acid (BF), which can be used as a substrate of enzymatic synthesis of (R)-(—)-mandelic acid, was investigated. Among 145 strains of yeasts and actinomycetes, Saccharomycopsis lipolytica (IAM 4964) was the best producer of BF from DL-phenylglycine (DL-PG). Culture conditions for BF production by the organism were optimized. When 0.2 % fructose as a carbon source and 0.7% Bacto-tryptone as a nitrogen source were used in the presence of 4 % dl-PG, 14.5 mg/ml of BF was produced (about 37 % molar yield) in 4 days of cultivation. BF was synthesized from the L-form of PG, but not from the D-form. The BF was isolated from culture broth in a crystalline form and physicochemically identified. © 1990, Japan Society for Bioscience, Biotechnology, and Agrochemistry. All rights reserved.

DOI： 10.1271/bbb1961.54.2101

Characterization of crystalline formate dehydrogenase from Candida methanolica

Yoshikazu IZUMI, Hiroshi KANZAKI, Shigeru MORITA, Hideaki FUTAZUKA, Hideaki YAMADA

European Journal of Biochemistry 182 ( 2 ) 333 - 341 1989

Language：English

The crystalline formate dehydrogenase from Candida methanolica, which showed the highest specific activity (7.52 U/mg) so far reported, was characterized in detail. The enzyme is a dimer composed of identifical subunits, each containing one SH group related to the catalytic activity. The molecular mass of the enzyme is about 82–86 kDa. The Km values were found to be 3.0 mM for formate and 0.11 mM for NAD+. Even if the enzyme was incubated at pH 6.5–9.5 or at 55°C, the activity remained at 100%. Hg2+, Ni2+, NaCN, NaN3 and p‐chloromercuribenzoate strongly inhibited the enzyme activity, while the enzyme showed relatively high resistance to various chelating agents. The amino acid composition and some other physicochemical properties of the enzyme were studied. Immunological studies revealed that formate dehydrogenases of methanol‐utilizing yeasts immunologically more or less resemble each other, but differ from those of methanol‐utilizing bacteria. Furthermore, yeast formate dehydrogenases can be immunologically classified into three types: (a) the Candida type, (b) the Torulopsis/Hansenula/Pichia type and (c) the formaldehyde‐resistant yeast type. For simple and large‐scale preparation of the enzyme for practical use, treatment of cells of C. methanolica with the commercial cationic detergent, ‘Benzalkonium’ cation, is useful: the total and specific activities of the enzyme are 1.17‐fold and 3.10‐fold higher than those of the crude cell‐free extract, respectively. Copyright © 1989, Wiley Blackwell. All rights reserved

DOI： 10.1111/j.1432-1033.1989.tb14835.x

Purification and characterization of cystathionine γ‐synthase type II from Bacillus sphaericus

Hiroshi KANZAKI, Michihiko KOBAYASHI, Toru NAGASAWA, Hideaki YAMADA

European Journal of Biochemistry 163 ( 1 ) 105 - 112 1987

Language：English

Cystathionine γ‐synthase type II, which catalyzes l‐cystathionine synthesis from O‐acetyl‐l‐homoserine and l‐cysteine was purified from Bacillus sphaericus (IFO 3536) in seven steps. The purified enzyme appeared to be homogeneous by the results of polyacrylamide electrophoresis and ampholyte electrofocusing. The enzyme is a typical pyridoxal‐P dependent enzyme, has a molecular mass of 165 kDa and consists of four subunits identical in molecular mass. The enzyme catalyzed the γ‐replacement reaction and the elimination reaction was hardly detected even when a large amount of enzyme was added. In the replacement reaction, O‐acetyl‐l‐homoserine and the following thiol compounds: L and d‐cysteine, L and d‐homocysteine, sodium sulfide, various alkyl and aryl mercaptans, acted as the most suitable substrate to produce l‐cystathionine and the corresponding S‐substituted l‐homocysteine derivatives. Copyright © 1987, Wiley Blackwell. All rights reserved

DOI： 10.1111/j.1432-1033.1987.tb10742.x

Purification and characterization of cystathionine γ‐synthase type II from Bacillus sphaericus

Hiroshi KANZAKI, Michihiko KOBAYASHI, Toru NAGASAWA, Hideaki YAMADA

European Journal of Biochemistry 163 ( 1 ) 105 - 112 1987

Language：English

Cystathionine γ‐synthase type II, which catalyzes l‐cystathionine synthesis from O‐acetyl‐l‐homoserine and l‐cysteine was purified from Bacillus sphaericus (IFO 3536) in seven steps. The purified enzyme appeared to be homogeneous by the results of polyacrylamide electrophoresis and ampholyte electrofocusing. The enzyme is a typical pyridoxal‐P dependent enzyme, has a molecular mass of 165 kDa and consists of four subunits identical in molecular mass. The enzyme catalyzed the γ‐replacement reaction and the elimination reaction was hardly detected even when a large amount of enzyme was added. In the replacement reaction, O‐acetyl‐l‐homoserine and the following thiol compounds: L and d‐cysteine, L and d‐homocysteine, sodium sulfide, various alkyl and aryl mercaptans, acted as the most suitable substrate to produce l‐cystathionine and the corresponding S‐substituted l‐homocysteine derivatives. Copyright © 1987, Wiley Blackwell. All rights reserved

DOI： 10.1111/j.1432-1033.1987.tb10742.x

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