• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.399-404
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• 2010

A hydrogen-producing bacterium (strain ES392) was isolated from pond water located in the Dong-Eui University, Busan, Korea. The cell was long-rod type ($1.4\;{\mu}m$) of about ($0.6\;{\mu}m$) in diameter, and not formed flagellum and spore. Phylogenetic analysis based on the 16S rRNA sequence and biochemical studies indicated that ES392 belonged to the genus Enterobacter sp. The optimum pH and temperature for hydrogen production was 7.5 and $35^{\circ}C$, respectively. The optimization of medium compositions which maximize hydrogen production from Enterobacter sp. ES392 was determined. As a result, the maximum hydrogen production was obtained under the conditions of 4% (w/v) sucrose, 0.5% (w/v) yeast extract and 50 mM potassium phosphate buffer (pH 7.5). Under batch culture conditions, the maximal hydrogen production and yield were obtained as 3481 mL/L and 1.33 mol/mol sucrose, respectively.

• Microbiology and Biotechnology Letters
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• v.40 no.2
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• pp.135-143
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• 2012

This study's aim is to isolate and characterize plant growth promoting Enterobacter species for the biological control of gray leaf spot in pepper. Screening was carried out from the rhizosphere of Agropyron tsukushiensi var. transiens (Hack.) Ohwi in Dok-do. Rhizobacterial isolates were partially identified by 16S rDNA sequencing and Enterobacter species were tested for plant growth promoting capabilities and the induction of systemic resistance in pepper against gray leaf spot caused by Stemphylium solani. Isolates were tested for production of indole-acetic acid and siderophore, and for phosphate solubilization. The application of isolates was effective in controlling gray leaf spot in pepper with E. asburiae (KNUC5007) and E. cancerogenes (KNUC5008 and KNUC5010) having the highest efficacy in reducing gray leaf spot severity. This is the first report of the biological control of gray leaf spot in pepper using rhizobacteria and it is hoped that this study will increase the utilization of Enterobacter species as plant growth promoters and biocontrol agents.

• Applied Chemistry for Engineering
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• v.20 no.4
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• pp.449-452
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• 2009

The absence of Fe, Se, and Mo in a minimal medium prevented the production of hydrogen from the anaerobic culture of Escherichia coli MC4100. Fe, Se, and Mo are known to be cofactors of formate dehydrogenase ($FDH_{II}$) of both E. coli and Enterobacter aerogenes. Hence when these trace elements are absent in the minimal medium, hydrogen production through formate dehydrogenation would be inhibited not only in E. coli but also in E. aerogenes. Hydrogen production by E. aerogenes 413 was delayed when lacking these trace elements. Therefore, it is believed that hydrogen production of E. aerogenes is initiated not by the reoxidation of nicotinamide adenine dinucleotide (NADH) but by formate decarboxylation.

• Microbiology and Biotechnology Letters
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• v.21 no.1
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• pp.36-40
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• 1993

A bacterial strain, producing extracellular inulin fructotransferase which converts inulin into di-D-fructofuranose dianhydride (DFA) was isolated from soil and presumed as Enterobacter sp. The DFA isolated on Bio-gel P2 column was identified as DFA III by high performance liquid chromatography and $^13C-nmr$ spectroscopy. The enzyme production was induced by inulin and markedly enhanced by the addition of corn steep liquor and $NH_4H_2P0_4$ for nitrogen source. Under optimum condition, the enzyme activity in the culture broth reached at maximum, 0.22 unit/ml after cultivation for 72 hour.

• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.393-399
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• 1998

Enterobacter sp.B54 which shows antagonistic activity to Phytophthora capsici on potato dextrose agar was selected among 112 strains isolated from Korean soil. After Tn5 lac-induced mutants were obtained through Pl :: Tn5 lac mutagenesis, 2 mutants for loss of antibiosis and 1 mutant for increased antibiosis were screened by using in vitro fungal inhibition assay. When the 3 mutants affected in antibiosis were analyzed by southern hybridization with pRZ102 (ColEl :: Tn5) as a probe, its results suggest that Tn5 lac was randomly inserted into different chromosomal sites in these mutants.

• KSBB Journal
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• v.23 no.1
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• pp.54-58
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• 2008

Hydrogen is considered as an energy source for the future due to its environmentally friendly use in fuel cells. A promising way is the biological production of hydrogen by fermentation. In this study, the optimization of medium conditions which maximize hydrogen production from Enterobacter aerogenes KCCM 40146 were determined. As a result, the maximum attainable cumulative volume of hydrogen was 431 $m{\ell}$ under the conditions of 0.5M potassium phosphate buffer, pH 6.5 medium containing 30 g/L glucose. The best nitrogen sources were peptone and tryptone for the cell growth as well as hydrogen production. The control of cell growth rate was found to be a important experimental parameter for effective hydrogen production

• Microbiology and Biotechnology Letters
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• v.15 no.2
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• pp.116-121
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• 1987

In order to cloning of the nif genes of Enterobacter agglomerans NFB-264, the digested total DNA of the strain was ligated to pBR 322 and transformed into E. coli. Through the negative selection and colony hybridization, the transformants were obtained. The recombinant plasmids, pNEL 10 and pNES 20 were extracted from these transformants. It was known from Southern hybridization that pNEL 10 contained the 12 Mdal foreign DNA fragment hybridized with nif Q-X probe and pNES 20 included the 5 Mdal foreign DNA fragment hybridized with nif NE and nif YK probe.

• KSBB Journal
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• v.16 no.4
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• pp.370-375
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• 2001

For the production of new exo-biopolymers from microorganisms, an exe-biopolymer producing bacterial strain was isolated from the composter used in composting of organic wastes. Bacteriological properties of this strain and physicochemical properties of producing exo-biopolymer were investigated. The isolated strain was identified as Enterobacter sp. through its morphological, cultural and physiological characteristics. The results of color reactions, CPC (cetyl pyridinium chloride) precipitation and infra red absorption spectral analysis indicated that this exo-biopolymer was presumed as an acidic polysaccharide with uronic acid. This polysaccharide was identified as hetero-polysaccharide consisting of galactose, mannose and galacturonic acid by gas chromatography, and the molecular weight of exopolysaccharide purified by gel chromatography were about 370,000 daltons. The polysaccharide solutions(0.50-2.0%, w/v) exhibited non-Newtonian flow behavior with pseudoplastic property and showed the ability of gel formation at above 1.5% (w/v) of polysaccharide concentration.

• Korean Journal of Microbiology
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• v.26 no.1
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• pp.20-26
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• 1988

Three $NIf^{-}$ -mutants were isolated from Enterbacter agglomerans 339 through the transposon umtagenesis using a RP4-mobilising system for its nif-gene characterization. All mutants hadn't acetylene-reduction ability. Then we confirmed that Tn5 was inserted into all conserved nif-plasmids through the Southern Hybridization.

• Microbiology and Biotechnology Letters
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• v.51 no.3
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• pp.306-308
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• 2023

This research presents the whole-genome sequence of Enterobacter asburiae strain IK3, which was isolated from the rhizosphere soil of soybean (Glycine max). The genome of the strain is composed of a single chromosome with 4 plasmids, total size of 5,084,040 bp, and the GC content is 55.5%.