• The Microorganisms and Industry
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• v.18 no.3
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• pp.23-33
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• 1992

The general characteristics of campylobacters and related organisms (e.g., species of the genera Helicobacter and Wolinella, Bacteroides ureolyticus, and Bacteroides gracilis) are as follows: slender, non-sporeforming, gram-negative, vibroid bacteria (helical- or spiral- shpaed; except that B. ureolyticus and B. gracilis are straight-rod), 0.2-0.5 .mu.m in width and 0.5 .mu.m in length. (Smibert, 1984; Penner, 1988). The species of genus Campylobacter and related organisms are chemoorganotrophs; however, they neither oxidize nor ferment carbohydrates and instead obtain energy from amino acids, the salts of tricarboxylic acids (TCA) cycle intermediates, the salts of organic acids, or, in some species, H$\_$2/. With regard to their oxygen responses for growth, they all are microaeophilic i.e., they are capable of oxygen-dependent growth (respiring with oxygen as a terminal electron acceptor) but can not grow in the presence of a level of oxygen equivalent to that present in an air atmosphere (21% oxygen). This review will take interests in how these microorganisms response to oxygen for growth and what repiratory types they have.

• Microbiology and Biotechnology Letters
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• v.21 no.5
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• pp.414-420
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• 1993

Escherichia coli mrdAts and mrdBts mutants forming spherical cells at 42C, were employed to investigate the possible role of both inner and outer membrance structures in the determination of cell shape of gram-negative cells. Spherical cells, but not rod-shaped wild types, were specifically killed by anionic detergents, such as sarkosyl, sodium dodecylsulfate and sodium deoxycholate. From the spherical intact cells grown overnight at 42C, much more proteins were released by sakosyl.

• Journal of Microbiology and Biotechnology
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• v.10 no.5
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• pp.724-727
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• 2000

A Phenanthrene-degrading bacterium, Strain 1-21 was isolated from oil-contaminated soil. This strain was a Gram-negative, aerobic, and rod-shaped bacterium, and exhibited a 99% sequence similarity of 16S rDNA to that of Sphingomonas subarctica. The major cellular fatty acid was a summed feature 7(18:1 w7c, 18:1 w9t, 18:1 s12t), which is a characteristic of the Sphingomonas species. When 200 and 1,000 ppm of phenanthrene was added as the sole carbon source, Strain 1-21 degraded 98% and 67% after 10 days of incubation, respectively. Futhermore, this strain was also able to utilized naphthalene and fluorene as sole carbon and energy sources.

• Journal of Microbiology
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• v.35 no.3
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• pp.188-192
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• 1997

The strain of S-47 degrading 4-chlorobenzoic acid (4CBA) was isolated from Ulsan chemical industrial complex by enrichment cultivation with 1 mM 4CBA. The strain was Gram-negative rod and grew optimally at 30.deg.C and pH 7 under aerobic condition, so that the organism was identified as a species of Pseudomonas. Pseudomonas sp. S-47 degraded 4-chlorobenzoic acid to produce a yellow-colored meta-cleavage product, which was confirmed to be 5-chloro-2-hydroxymuconic semialdehyde (5C-2HMS) by UV-visible spectrophotometry. 5C-3HMS was proved trometry. This means that Pseudomonas sp. S-47 degraded 4CBA via 4-chlorocatechol to 5C-2HMS by meta-cleavage reaction and then to 5C-2HMA by 5C-2HMS dehydrogenase.

• Electrolytes & blood pressure
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• v.16 no.2
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• pp.27-29
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• 2018

Peritoneal dialysis (PD)-related peritonitis is a major cause of injury and technique failure in patients undergoing PD. Aeromonas hydrophila is ubiquitous in the environment, and is a Gram-negative rod associated with infections in fish and amphibians in most cases; however, it can also cause opportunistic infections in immunocompromised patients. We report a case of A. hydrophila peritonitis in a 56-year-old male on automated PD. Peritonitis may have been caused by contamination of the Set Plus, a component of the automated peritoneal dialysis device. Although Set Plus is disposable, the patient reused the product by cleansing with tap water. He was successfully treated with intraperitoneally-administered ceftazidime and has been well without recurrence for more than 2 years.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.503-508
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• 2005

Screening for antilisterial activity was performed in about three thousand isolates of lactic acid bacteria (LAB) from Chinese cabbage kimchi, and finally based on the relatively stronger antilisterial activities eight bacterial strains were selected. The bacteria were further characterized in terms of their tolerance to artificial gastric juice, pH 2.5, bile salts (0.3% oxgall), and to the different NaCl concentrations. Of the isolates, YK005 was especially investigated for its physiological characteristics due to its inhibitory activity against gram-positive Listeria monocytogenes as well as gram-negative Escherichia coli O157:H7, as they have been constantly reported to be resistant against bacteriocins produced by a number of LAB strains. YK005 was found to be rod-shaped, $3.8\;{\mu}m$ long ${\times}\;0.5\;{\mu}m$ wide, non-sporeforming, non-motile, catalase-negative, and produced gas from glucose (heterolactic). Based on the biochemical data obtained by API 50 CHL medium, the isolate was tentatively identified as Lactobacillus brevis. To validate the result obtained by the biochemical identification, rRNA-based PCR experiments using a pair of species-specific primers for L. brevis were conducted and a single band of 1400 bp was observed, which strongly indicated that YK005 belongs to L. brevis. The LAB isolates are potentially exploited as human probiotic organisms and are employed to control some food-borne pathogens like L. monocytogenes.

• Korean Journal of Microbiology
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• v.50 no.2
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• pp.152-157
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• 2014

The aim of this study was to investigate the bacterial community inhabited in Callyspongia elegans. Marine bacteria were isolated from the marine sponge C. elegans using marine agar. The resulting 112 isolated pure cultures were then used for further study. They were characterized by determining morphological characteristics through Gram's staining and morphological observation. The colony pigments of bacterial isolates were characterized as yellow, brown, ivory, and white. Thirty-seven strains were found to be Gram-positive and 75 strains were Gram-negative. Seventy-nine strains were coccus-shaped, while 16 strains were rod-shaped. On the basis of the results of the comparative analyses of 16S rDNA gene sequences, the 112 isolated bacteria were divided into 5 major groups: Alphaproteobacteria (39%), Gammaproteobacteria (22%), Actinobacteria (14%), Fimicutes (9%), and Bacteroidetes (6%). It is strongly suggested that fifteen isolates are candidates for a new genera or species, based on the analyses of 16S rDNA gene sequences.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.509-516
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• 2007

Starters of lactic acid bacteria(LAB) were isolated from the commercial yoghurt products and the four isolates have been studied on their identification and some physiological characteristics. For the purpose of identification, microscopic examination, API test, and 16s rRNA gene sequencing were conducted. Isolate A from a yogurt product of local dairy company A was shown to be Gram-positive rod-shaped bacterium. All strains isolated were turned out to be as Lactobacillus paracasei by using a API 50 CHL kit. In contrast, isolate A was identified as a strain of Lactobacillus helveticus based on the 16S rRNA sequencing data, and L. casei ssp. casei for both B and D and L. paracasei for C. All the isolates survived the simulated gastric juice, pH 2.0 within 3 hours and sharply decreased in viability so that no viable cell was observed after 4.5 hours incubation. In addition, the four isolated strains were almost identical in antibiotic susceptibility to six different kinds of antibiotics including erythromycin ($15\;{\mu}g$), ampicillin ($10\;{\mu}g$), gentamycin ($10\;{\mu}g$), neomycin ($30\;{\mu}g$), but rather resistant to colistin ($10\;{\mu}g$) and streptomycin ($10\;{\mu}g$). It was noteworthy that four isolates were confirmed to produce antibacterial substance against foodborne pathogens of Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli 0157:H7 as test organisms based on the inhibitory zones on an MRS soft agar medium. At presence, the inhibitory factor is unknown so that further studies are required to ascertain the active factor responsible for the inhibitory activities.

• Journal of Species Research
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• v.8 no.2
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• pp.176-190
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• 2019

A total of 38 bacterial strains within the classes Bacilli and Deinococci were isolated from various sources in Korea. Samples were collected from animal intestine, urine, soil, tidal flat mud, and kimchi. In the sequence comparison and phylogenetic analysis of 16S rRNA sequences, the 38 isolates were assigned to the classes Bacilli and Deinococci with sequence similarities more than 98.7%. Twenty-four strains and 13 strains were classified the order Bacillales and Lactobacillales in the class Bacilli, respectively. In the order Bacillales, there were nine species in the genus Bacillus, seven species in the genus Paenibacillus, and the remaining eight species in the genera Domibacillus, Halobacillus, Virgibacillus, Lysinibacillus, Paenisporosarcina, Planococcus, Savagea, and Staphylococcus. In the order Lactobacillales, there were four species in the genus Lactobacillus, three species in the genus Leuconostoc, three species in the genus Lactococcus, and the remaining three species in the genera Aerococcus, Enterococcus, and Streptococcus. One species was related to the genus Deinococcus of the order Deinococcales. Most of the isolated strains were Gram-stain-positive, but some were Gram-stain-variable or Gram-stain-negative. Cells were rod or cocci-shaped. Based on the results of 16S rRNA analysis, we report 38 strains as previously unrecorded species to Korea, and the basic characteristics of strains are described herein.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.1-7
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• 1999

The grain rot of caused by Bukholderia glumae was fist reported in japan in 1955 and then reported in other countries as well as in Korea in 1986. The pathogen causes both seedling and grain rot of rice but it cannot attack any other parts of adult rice plant. Bacterial colonies grow slowly, and are circular and greyish white. The causal bacterium is Gram-negative and rod shape with 1-3 polar flagella, and produce a diffusible yellow-greenish nonfluorescent pigment on King's medium B. Biochemical characteristics such as negative in arginine dehydrolase, oxidase reaction and nitrate reduction and positive in lecithinase, and the utilization of L-arginine and inositol are useful in differentiation of this from other nonfluorescent bacteria pathogenic to rice. This pathogenic bacterium had belonged to the genus of Pseudomonas but recently was transferred to the new genus Burkholderia on the basis of physiological characteristics and DNA-DNA hybridization data. However, other characteristics such as colony heterogenicity or colonial variation after subcultures, phytotoxin, secreting antibiotics, and relationship between yellow greenish pigment production and pathogenicity need to be clarified more. To develop an effective control strategy for this disease, understanding of detailed life cycle of the disease and critical environmental factors affecting disease development is prerequisite. Although 5,435 ha of rice paddy in Korea was infested during 1998, there is no exact estimation of yield losses and distribution of the pathogen. The review will focus on recent progress on the understanding of the bacteriological and ecological characteristics of the causal bacterium and control means of the disease.