著者
TETSUO HIYAMA SHOJI MIZUSHIMA KAKUO KITAHARA
出版者
公益財団法人 応用微生物学・分子細胞生物学研究奨励会
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
vol.11, no.1, pp.51-60, 1965 (Released:2006-08-11)
参考文献数
15
被引用文献数
4 7

As a result of quantitative studies, the racemization of lactate in Loctobacillus plantarum was found to be a cooperative reaction catalyzed by NAD-linked D- and L-lactate dehydrogenases. Any positive evidence of the existence of lactate racemase as a single enzyme in this organism could not be obtained. The former "Racemiase" is concluded to be a mixture of two enzymes.
著者
Hiroshi Kobayashi Hiromi Saito Tomohito Kakegawa
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
vol.46, no.5, pp.235-243, 2000 (Released:2005-11-04)
参考文献数
73
被引用文献数
31 32

Bacteria can inhabit a wide range of environmental conditions, including extremes in pH ranging from 1 to 11. The primary strategy employed by bacteria in acidic environments is to maintain a constant cytoplasmic pH value. However, many data demonstrate that bacteria can grow under conditions in which pH values are out of the range in which cytoplasmic pH is kept constant. Based on these observations, a novel notion was proposed that bacteria have strategies to survive even if the cytoplasm is acidified by low external pH. Under these conditions, bacteria are obliged to use acid-resistant systems, implying that multiple systems having the same physiological role are operating at different cytoplasmic pH values. If this is true, it is quite likely that bacteria have genes that are induced by environmental stimuli under different pH conditions. In fact, acid-inducible genes often respond to another factor(s) besides pH. Furthermore, distinct genes might be required for growth or survival at acid pH under different environmental conditions because functions of many systems are dependent on external conditions. Systems operating at acid pH have been described to date, but numerous genes remain to be identified that function to protect bacteria from an acid challenge. Identification and analysis of these genes is critical, not only to elucidate bacterial physiology, but also to increase the understanding of bacterial pathogenesis.
著者
Marta Sochocka Tomasz Tomczyk Maciej Sobczyński Bożena Szermer-Olearnik Janusz Boratyński
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
vol.61, no.3, pp.75-81, 2015-06-30 (Released:2015-07-29)
参考文献数
36
被引用文献数
5 7

The aim of this study was to develop a minimal medium for the cultivation of Escherichia coli B, which could be especially suitable for the industrial propagation of bacteriophage T4. The new defined, minimal SM-1 culture medium, contains free amino acids as the only nitrogen source and enables the bacteria generation time to be prolonged and satisfactory phage titers to be achieved. The presence of organic ingredients, such as meat extracts, yeast hydrolysates, enzymatic protein hydrolysates, in a culture medium may cause problems in the case of bacteria or phage cultures for therapeutic purposes. In the present study, we introduce a new medium, together with some procedures and applications for its usage. We also present new kinetics of E. coli B growth. Some traits such as the lack of high molecular proteins, a bacterial growth comparable to that in a rich medium, and the cost effectiveness of the medium, makes it highly competitive with currently used microbiological media. The surprisingly high titers of bacteriophage T4 obtained in our experiments suggest that SM-1 medium has the potential to find a broad application in medicine, especially in infectious disease therapy, pharmacy and biotechnology.
著者
YOKO YAMAMOTO ATSUSHI WATANABE
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
vol.20, no.2, pp.83-86, 1974 (Released:2006-08-16)
参考文献数
8
被引用文献数
14 16

The fatty acid composition of lichens and their symbionts was determined. In lichens, linoleic and oleic acids were the most abundant and these acids were also rich in their phyco- and mycobionts. A small amount of arachidonic acid was detected in some of the lichens and their phyco- and mycobionts.
著者
Hazuki Hasegawa Kan Tanaka
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
pp.2023.02.001, (Released:2023-02-17)
参考文献数
20

Certain mutations of the model cyanobacterium Synechococcus elongatus PCC 7942 during laboratory storage have resulted in some divergent phenotypes. One laboratory stored strain (H1) shows a temperature-sensitive (ts) growth phenotype at 40 °C. Here, we investigated the reason for this temperature sensitivity. Whole genome sequencing of H1 identified a single nucleotide mutation in synpcc7942_R0040 encoding tRNA-Leu(CAA). The mutation decreases the length of the tRNA-Leu t-arm from 5 to 4 base pairs, and this explains the ts phenotype. Secondary mutations suppressing the ts phenotype were identified in synpcc7942_1640, which putatively encodes a NYN domain-containing protein (nynA). The NYN domain is thought to be involved in tRNA/rRNA degradation. Thus, the structural stability of tRNA-Leu is critical for growth at 40 °C in Synechococcus elongatus PCC 7942.
著者
Hidetoshi Inoue Kumiko Tajima Cristina Mitsumori Natsuko Inoue-Kashino Takamasa Miura Kentaro Ifuku Ryuichi Hirota Yasuhiro Kashino Katsutoshi Fujita Hiroshi Kinoshita
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
vol.68, no.3, pp.151-162, 2022 (Released:2022-11-10)
参考文献数
36
被引用文献数
1

A genetically modified (GM) strain of the diatom Chaetoceros gracilis expressing the phosphite dehydrogenase gene (ptxD), which is a useful gene both for the biological containment and the avoidance of microbial contamination, was characterized to estimate the risk against the biodiversity by laboratory experiments. GM strain could grow in the medium containing phosphite as a sole source of phosphorus, while its general characteristics such as growth, salt tolerance, heat and dehydration resistance in the normal phosphate-containing medium were equivalent to those of wild type (WT) strain. The increase in potential toxicity of GM strain against plant, crustacean, fish and mammal was also disproved. The dispersal ability of WT strain cultured in an outdoor raceway pond was investigated for 28 days by detecting the psb31 gene in vessels, settled at variable distances (between 5 and 60 m) from the pond. The diatom was detected only in one vessel placed 5 m apart. To estimate the influence on the environment, WT and GM strains were inoculated into freshwater, seawater and soil. The influence on the microbiome in those samples was assessed by 16S rRNA gene amplicon sequencing, in addition to the analysis of the survivability of those strains in the freshwater and the seawater. The results indicated that the effect to the microbiome and the survivability were comparable between WT and GM strains. All results showed that the introduction of the ptxD gene into the diatom had a low risk on biodiversity.
著者
MONIKA ZIPPEL MARLIES NEIGENFIND
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
vol.34, no.1, pp.7-14, 1988 (Released:2006-08-18)
参考文献数
20
被引用文献数
1 7

Three methods for preserving 16 Streptornyces strains were tested: lyophilization on soil and storage in frozen glycerol medium (-20°C), and in liquid nitrogen (-196°C) in the presence of dimethyl sulfoxide. The viability, stability of auxotrophic markers, antibiotic production, and resistance to their own antibiotics for a period up to one year were studied. No variations in the production of and resistance to antibiotics or accumulation of revertants of mutants were evident during the toral preservation time in all three storage methods. A drastic decrease in viable counts was observed after lyophilization on soil. Viability of strains frozen in glycerol and after storage in liquid nitrogen was similar and ranged from 2.3% to 36.6%.Storage of streptomycetes in frozen glycerol is recommended as a quick and reliable method for frequent studies in the laboratory. Storage in liquid nitrogen is recommended as a long-term preservation method.
著者
Yoshihiro Watanabe Yurika Yoshida Toshiyuki Tokiwa Mayuka Higo Sayaka Ban Akari Ikeda Yoshihiko Noguchi Tomoyasu Hirose Toshiaki Sunazuka Kenichi Nonaka Takashi Yaguchi Masato Iwatsuki
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
pp.2022.03.002, (Released:2022-05-20)
参考文献数
15
被引用文献数
3

A new antifungal polyketide, named hakuhybotric acid (1), was isolated from a cultured broth of a mycoparasitic fungus Hypomyces pseudocorticiicola FKI-9008, together with two known analogs, F2928-1 (2) and Cladobotric acid E (3). Their structures were elucidated by MS and NMR analyses. The structure of hakuhybotric acid was the two epoxy groups of F2928-1 converted to olefins. All compounds showed antifungal activity against four different species of Aspergillus spp., the causative agents of aspergillosis. It was suggested that mycoparasitic fungi are a useful source to search antifungal drug lead compounds.
著者
Hiroshi Kadokura Hiroyuki Kawasaki Koji Yoda Makari Yamasaki Katsuhiko Kitamoto
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
vol.47, no.3, pp.133-141, 2001 (Released:2005-12-26)
参考文献数
28
被引用文献数
11 14

Escherichia coli DegP is an inducible serine protease which is involved in the breakdown of abberant proteins arising in the periplasmic compartment. Overexpression of alkaline phosphatase (PhoA) increased transcription of degP by twofold. To examine the significance of its induction, we overexpressed PhoA in a mutant strain deficient in the degP gene. Upon PhoA overexpression, the degP mutant produced a smaller amount of active PhoA, about one half of the enzymatic activity of its isogenic wild-type strain, and accumulated a larger amount of its precursor, indicating that degP is required for efficient export of overexpressed PhoA. Pulse-chase experiment showed that PhoA overexpression in the absence of degP causes a severe defect in the export of several proteins tested. Examination of the synthesis and the accumulation of the phoA gene products revealed that a part of them, synthesized in the wild-type strain, undergoes relatively rapid proteolysis and that degP is necessary for such a process. From these results, we discuss a possible role of DegP in facilitating protein export under stress conditions.
著者
Wataru Nagahashi Naoko Yoshida
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
pp.2021.05.001, (Released:2021-08-31)
参考文献数
52
被引用文献数
6

In this study, two fibrous carbon anodes (namely, pleated non-woven graphite (PNWG) and carbon brush (CB) made from artificial carbon) and bamboo charcoal (BC) were evaluated for current recovery from sewage wastewater. When these anodes were polarized at 0.2 V vs. Ag/AgCl in sewage wastewater, CB produced a maximum current of 2.9 A/m2. This exceeded that produced by PNWG (1.5 A/m2) and BC (1.4 A/m2). The accumulative charge recovery achieved with CB was superior to those achieved with the other two (1.6- and 2.2-fold higher than that with PNWG and BC, respectively). During the cyclic voltammetry analysis, CB demonstrated the highest catalytic current with maximum potential in the range of –0.6 to 0.4 V vs. Ag/AgCl and the smallest anode resistance (0.20 Ωm2). Direct cell counting revealed that the fibrous anodes (CB and PNWG) attached most of the cells in the anodes (80%), whereas BC did not. In contrast, the proportion of Geobacter species, a representative electrogenic microorganism in the total bacteria, was observed to be similar among the three anodes (4.4–5.8%). The tubular microbial fuel cell (ø 5.0 cm) equipped with an air-chamber core wrapped with an anion exchange membrane (AEM) and the CB delivered a current of 1.8 A/m2. This is higher than those reported in the existing literature for the same microbial fuel cell (MFC) configuration. This indicates that the alteration of the anode from planar to brush can contribute toward improving the current recovery through the air-cathode-AEM-MFC. The BC needs improvement to have more specific surface area, whereas it showed superiority in cost efficiency considering material and processing.
著者
Shinya Yoshikawa Yu Kanesaki Akira Uemura Kazumasa Yamada Maiko Okajima Tatsuo Kaneko Kaori Ohki
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
pp.2021.02.002, (Released:2021-07-10)
参考文献数
34
被引用文献数
3

A unicellular cyanobacterium that produces a large amount of exopolysaccharide (EPS) was isolated. The isolate, named Chroococcus sp. FPU101, grew between 20 and 30°C and at light intensities between 10 and 80 μmol m–2 s–1. Purified EPS from Chroococcus sp. FPU101 had a molecular size of 5.9 × 103 kDa and contained galactose, rhamnose, fucose, xylose, mannose, glucose, galacturonic acid, and glucuronic acid at a molar ratio of 17.2:15.9:14.1:11.0:9.6:9.5:13.0:9.7. The EPS content significantly increased when the NaCl concentration in the medium was increased from 1.7 to 100 mM. However, high NaCl concentrations did not significantly affect the molecular size or chemical composition of the EPS. The genes wza, wzb, wzc, wzx, wzy, and wzz that are involved in EPS synthesis were conserved in the genome of Chroococcus sp. FPU101, which was sequenced in this study. These results suggest that the Wzy-dependent pathway is potentially involved in EPS production in this organism.
著者
Nobushige Nakazawa Mami Fukuda Mizuki Ashizaki Yukari Shibata Keitaro Takahashi
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
pp.2020.11.002, (Released:2021-06-19)
参考文献数
41
被引用文献数
1

The supply of oven-fresh bakery products to consumers has been improved by frozen dough technology; however, freeze-thaw stress decreases the activity of yeast cells. To breed better baker's yeasts for frozen dough, it is important to understand the factors affecting freeze-thaw stress tolerance in baker's yeast. We analyzed the stress response in IB1411, a spore clone from Saccharomyces cerevisiae Shirakami kodama yeast, with an exceptionally high tolerance to freeze-thaw stress. Genes encoding trehalose-6-phosphate synthase (TPS1), catalase (CTT1), and disaggregase (HSP104) were highly expressed in IB1411 cells even under conditions of non-stress. The expression of Hsp104 protein was also higher in IB1411 cells even under non-stress conditions. Deletion of HSP104 (hsp104Δ) in IB1411 cells reduced the activity of the ubiquitin-proteasome system (UPS). By monitoring the accumulation of aggregated proteins using the ΔssCPY*-GFP fusion protein under freeze-thaw stress or treatment with proteasomal inhibitor, we found that IB1411 cells resolved aggregated proteins faster than the hsp104Δ strain. Thus, Hsp104 seems to contribute to freeze-thaw tolerance by maintaining UPS activity via the disaggregation of aggregated proteins. Lastly, we found that the IB1411 cells maintained high leavening ability in frozen dough as compared with the parental strain, Shirakami kodama yeast, and thus will be useful for making bread.
著者
TAKASHI NAKASE GEN OKADA JUNTA SUGIYAMA MUTSUMI ITOH MOTOFUMI SUZUKI
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
vol.35, no.4, pp.289-309, 1989 (Released:2006-08-18)
参考文献数
47
被引用文献数
10 13

A new genus Ballistosporomyces Nakase, Okada et Sugiyama in the Hyphomycetes is described for yeasts that reproduce by both non-ballistosporous conidia and ballistospores, but not by budding yeast cells. Non-ballistosporous conidia are produced on a sterigma-like stalk which proliferates sympodially or percurrently. Strains in this genus have Q-10 as the major isoprenologue of ubiquinone, do not contain xylose in the cells, and show positive Diazonium blue B reaction. Two new species, Ballistosporomyces xanthus (type species) and B. ruber, are described in the genus. Ballistosporomyces xanthus has a G+C content of DNA of 62.1mol% and forms yellow colonies, whereas B. ruber has a G+C content of DNA of 50.8mol% and forms red colonies. Some properties of the new genus indicate a Ustilaginale affinity. Ontogenetic and chemotaxonomic comparisons are made between Ballistosporomyces and other supposedly related basidiomycetous yeast genera.
著者
Yoshio Kimura Sayaka Kajimoto Yuuka Yamamoto Naotaka Tanaka
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
vol.66, no.1, pp.46-50, 2020 (Released:2020-04-13)
参考文献数
22
被引用文献数
1 3

Myxococcus xanthus Nudix hydrolase 2 (Nud2) hydrolyzed oxidized deoxynucleotides, such as 8-oxo-dGTP, 8-oxo-dGDP, 8-OH-dTP, and 2-OH-dATP, and showed the highest specific activity toward 8-oxo-dGTP. Mn2+ was the most effective co-factor for stimulating oxidized deoxynucleotide hydrolase activity. The Km of Nud2 with 8-oxo-dGTP for Mn2+ was 19-fold lower than that for Mg2+, and was 2-fold lower than that with dGTP for Mn2+. The specificity constant (kcat/Km) for 8-oxo-dGTP was 6-fold higher than that for dGTP. Nud2 contains a similar Nudix motif (84AX590GX7REX2EEXGX). Replacement of Ala84 and/or Gly90 in the Nudix motif of Nud2 by Gly or Glu had negligible effects on 8-oxo-dGTP hydrolase activity, suggesting that a strict Nudix motif sequence is not essential for complete hydrolase activity of Nud2.
著者
KODAMA KENKICHI KYONO TADASHI KODAMA SHOJIRO
出版者
公益財団法人 応用微生物学・分子細胞生物学研究奨励会
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
vol.8, no.1, pp.52-55, 1962
被引用文献数
5

A new species of yeast belonging to the Genus <i>Pichia</i> Hansen was isolated from exudation of a tree stump, (<i>Carpinus</i> spec.) in Japan. The name <i>Pichia saitoi</i> was proposed for this microorganism. A characteristic feature of this species is in its unique shape of ascospores.
著者
Masakazu Saito Satoru Watanabe Kaori Nimura-Matsune Hirofumi Yoshikawa Hitoshi Nakamoto
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
pp.2020.02.001, (Released:2020-04-10)
参考文献数
29
被引用文献数
1

The CIRCE/HrcA system is highly conserved in cyanobacterial genomes. We have shown that heat-shock induction of the groESL1 operon in the cyanobacterium Synechocystis sp. PCC6803 is negatively regulated by the CIRCE/HrcA system. In Synechococcus elongatus PCC7942, a novel heat shock protein, Orf7.5, is involved in positive regulation of the groESL1 transcription. However, Orf7.5 is not conserved in some cyanobacteria, including Synechocystis sp. PCC6803. The purpose of this study is to evaluate the functional conservation of the CIRCE/HrcA system in S. elongatus PCC7942 and to understand the interplay between the CIRCE/HrcA system and the Orf7.5 regulatory system. We constructed single and double mutants of S. elongatus orf7.5, hrcA and orf7.5/hrcA and heat induction of the groESL1 transcription in these mutants was analyzed. Unexpectedly, derepression of the groESL1 transcription in an hrcA mutant was not observed. In all these mutants, the transcription was greatly suppressed under both normal and heat stress conditions, indicating that both HrcA and Orf7.5 are involved in regulation of the groESL1 transcription in a positive way. Consistent with the decrease in the groESL1 mRNA level, all the single and double mutants showed a great loss of acquired thermotolerance. Heat induction of the orf7.5 promoter activity was totally diminished in the orf7.5 mutant, indicating that Orf7.5 activates its own transcription. Yeast two hybrid analysis showed that the principle sigma factor RpoD1 interacts with Orf7.5. These results indicate that Orf7.5 enhances the transcription of groESL1 and orf7.5 by interacting with RpoD1.
著者
Haruki Yamamoto Hiroko Kojima-Ando Kaori Ohki Yuichi Fujita
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
pp.2020.01.009, (Released:2020-04-02)
参考文献数
62
被引用文献数
8

Protochlorophyllide (Pchlide) reduction is the penultimate step of chlorophyll (Chl) biosynthesis, and is catalyzed by two evolutionarily unrelated enzymes: dark-operative Pchlide oxidoreductase (DPOR) and light-dependent Pchlide oxidoreductase (LPOR). Because LPOR is the sole Pchlide reductase in angiosperms, dark-grown seedlings of angiosperms become etiolated. LPOR exists as a ternary complex of Pchlide-NADPH-LPOR to form paracrystalline prolamellar bodies (PLBs) in etioplasts. Because LPOR is distributed ubiquitously across oxygenic phototrophs including cyanobacteria, it would be important to determine whether cyanobacterial LPOR has the ability to form PLBs. We isolated a DPOR-less transformant ΔchlL/LPORox, carrying a plasmid to overexpress cyanobacterial LPOR in the cyanobacterium Leptolyngbya boryana. The transformant did not produce Chl in the dark and became etiolated with an accumulation of Pchlide and LPOR. Novel PLB-like ultrastructures were observed in etiolated cells, which disappeared during the early stage of the light-dependent greening process. However, the rate of Chl production in the greening process of ΔchlL/LPORox was almost the same as that observed in the control cells, which carried an empty vector. An in vitro LPOR assay of extracts of dark-grown ΔchlL/LPORox cells suggested that the PLB-like structures are deficient in NADPH. Low-temperature fluorescence emission spectra of membrane fractions of the etiolated cells indicated the absence of the photoactive form of Pchlide, which was consistent with the inefficiency of the greening process. Cyanobacterial LPOR exhibited an intrinsic ability to form PLB-like ultrastructures in the presence of the co-accumulation of Pchlide; however, the PLB-like structure differed from the authentic PLB regarding NADPH deficiency.
著者
Ayumi Kizawa Takashi Osanai
出版者
Applied Microbiology, Molecular and Cellular Biosciences Research Foundation
雑誌
The Journal of General and Applied Microbiology (ISSN:00221260)
巻号頁・発行日
pp.2020.01.004, (Released:2020-03-13)
参考文献数
34
被引用文献数
4

In photosynthetic microorganisms, cell cycle progression depends on day and night cycles; however, how cell division is regulated in response to these environmental changes is poorly understood. RpaA has been implicated in the signal output from both circadian clocks and light/dark conditions in the unicellular spherical-celled cyanobacterium Synechocystis sp. PCC 6803. In the present study, we investigated the involvement of a two-component response regulator RpaA in cell division regulation. Firstly, we examined the effects of rpaA overexpression on cell morphology and the expression levels of cell division genes. We observed an increase in the volume of non-dividing cells and a high proportion of dividing cells in rpaA-overexpressing strains by light microscopy. The expression levels of selected cell division-related genes were higher in the rpaA-overexpressing strain than in the wild type, including minD of the Min system; cdv3 and zipN, which encode two divisome components; and murB, murC, and pbp2, which are involved in peptidoglycan (PG) synthesis. Moreover, in the rpaA-overexpressing strain, the outer membrane and cell wall PG layer were not smooth, and the outer membrane was not clearly visible by transmission electron microscopy. These results demonstrated that rpaA overexpression causes an impaired cell division, which is accompanied by transcriptional activation of cell division genes and morphological changes in the PG layer and outer membrane.