• Journal of radiological science and technology
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• v.31 no.4
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• pp.329-335
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• 2008

Distribution of microorganisms were examined for the bucky tables in the radiology rooms of the department of radiological technology, the aprons, handles of various apparatus, handles of mobile radiological apparatus, and hands of the radiological technologists. As a result, relatively larger amounts of bacteria were found on the handles of the mobile radiological apparatus and the aprons. Among the isolated bacteria, Acinetobacter baumanni (7.3%), Klebsiella pneumoniae (6.7%), Staphylococcus aureus (3.9%), Serratia liquefaciens (1.7%), Enterobacter cloaceae (0.6%), Providenica rettgeri (0.6%) are known as the cause of nosocomial infection (hospital acquired infection). In addition, similar colonies were also found on the hands of the radiological technologists such as microorganisms of Klebsiella pneumoniae (8.4%), Staphylococcus aureus (6.6%), Yersinia enterocolotica (5.4%), Acinetobacter baumanni (4.2%), Enterobacter cloaceae (2.4%), Serratia liquefaciens (1.8%), Yersinia pseuotuberculosis (18%), Enterobacter sakazakii (1.2%), and Escherichia coli (0.6%). In particular, this result indicates clinical significance since Staphylococcus aureus and Escherichia coli show strong pathogenicity. Therefore, a continuous education is essential for the radiological technologists to prevent the nosocomial infection.

• Journal of fish pathology
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• v.6 no.2
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• pp.103-110
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• 1993

Total genomic DNA library of Serratia marcescens was prepared by inserting Sau3AI partial digesting fragments(above 5 kb) into the dephosphorylated BamHl site of pUC19. In primary screening, two colonies were selected by observing the halo around E. coli transformants grown on the swollen colloidal chitin media. Secondary screening was performed by soaking two colonies with a few drops of 4-methylumbelleliferryl N-acetyl-$\beta$-D-glucocosaminide(4-MuNGlcNAc). As 4-MuNGlcNAc is a specific, fluorogenic substrate for chitinase, the positive clones produce light fluorescence by the exposure under the long wave U.V. light(360 nm). From genomic DNA library derived from pUC19, we have isolated two different chitinase clones, pCH1(11.0Kb) and pCH2(7.5Kb), which show completely different restriction map to each other. The cross-hybridization of pCH1EA and pCH2 have not revealed any hybridization signals to each other.

• BMB Reports
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• v.34 no.2
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• pp.109-113
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• 2001

The Serratia marcescens metalloprotease inhibitor (SmaPI) is a proteinase inhibitor toward Serratia marcescens metalloprotease (SMP). The three-dimensional structure of SmaPI was calculated by computer modeling using the structure complex between SMP and the Erwinia chrysanthemi inhibitor as a template. Based on this model structure, the substitution of the amino acid residues, Ala4, Leu-5, Pro-6, and Thr-7, were located at the hinge region of the N-terminal segment by site-directed mutagenesis. Although the A4R and T7A mutant SmaPIs showed a nearly full inhibitory activity, the inhibitory activity of SmaPI decreased significantly when the Leu-5 was converted to Ala, Gly, Ile, or Val. Surprisingly, the L5I and L5V mutant SmaPIs showed less inhibitory activities than the L5A mutant. From these results, we suggested that the orientations and positions of respective aliphatic groups in the side-chain of position 5 mainly affected the inhibitory activity of SmaPI. The overall side-chain hydrophobicity was only slightly affected. The side-chain of the Leu-5 residue contributed approximately 0.79 kcal/mol out of 8.44 kcal/mol to the binding of SmaPI with SMP The inhibitory activities of P6A and F6G were also severely decreased. The Pro-6 may have a critical role in maintaining the strict conformation of the N-terminal portion that may be important in the inhibitory activity of SmaPI. In conclusion, Leu-5 and Pro-6 have crucial roles in the inhibitory function of SmaPI toward SMP.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.185-192
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• 1986

Antimicrobial susceptibility of the bacterial strains isolated from clinical specimens during the period from June, 1983 to June, 1986 in Yeungnam Medical Center was studied and the following results were obtained. 1. Staphylococcus aureus was highly susceptible to cephalothin and its susceptibility to methicillin was gradually reduced. 2. Streptococcus strains except enterococcus were generally susceptible to penicillin, while most enterococci were suscesceptible to only ampicillin. 3. Gram-negative rods including Escherichia coli were highly susceptible to amikacin and tobramycin. 4. Serratia were generally less susceptible to the amtimicrobials tested than other Enterobacteriaceae. Among them, Serratia marcescens showed the highest susceptibility to amikacin and chloramphenicol. 5. Pseudomonas aeruginosa revealed the highest susceptibility to amikacin and tobramycin and moderate susceptibility to carbenicillin and gentamycin. 6. Acinetobacter calcoaceticus revealed low susceptibility to most antimicrobials tested, showing only 30% susceptibility to amikacin, tobramycin and gentamycin in 1986.

• Journal of Microbiology and Biotechnology
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• v.19 no.2
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• pp.147-154
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• 2009

The carboxylesterase-encoding gene(bioHs) of a newly isolated strain, Serratia sp. SES-01, was cloned from the genomic DNA library by detecting formation of transparent halo around the colony on LB-tributyrin agar plates. The amino acid sequence of BioHs was highly similar to the members of the BioH enzyme family involved in the biotin biosynthetic pathway; it showed the highest similarity(91%) with that of Serratia proteamaculans. To compare BioHs with other BioH enzymes, the relatively well-known bioHe gene of E. coli was cloned with PCR. After we achieved high-level expression of soluble BioHs and BioHe through the exploration of different culture conditions, the purified BioHs and BioHe enzymes were characterized in terms of specificity, activity, and stability. BioHe was generally more robust to a change in temperature and pH and an addition of organic solvents than BioHs. The two enzymes exhibited a strong preference for carboxylesterase rather than for thioesterase and were optimal at relatively low temperatures($20-40^{\circ}C$) and alkaline pHs(7.5-9.0). The results in this study strongly suggested that both the BioHs and BioHe enzymes would be potential candidates for use as a carboxylesterase in many industrial applications.

• Research in Plant Disease
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• v.10 no.1
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• pp.63-68
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• 2004

Twenty-three strains of Serratia sp., isolated from surface-sterilized rice roots collected in Chonbuk and Chungnam province, were identified and characterized. They were Gram-negative, rod shaped and red pigmented typically and their endophytism was confirmed by inoculation and reisolation of the strains in planta. Their antifungal activity against 4 rice pathogenic fungi was compared and ranged from 62.4 to 85.2％ against Rhizoctonia solani and 68.0 to 88.5％ against Pyricularia grisea. Among the 23 strains tested, strain Rsm220 showed the strongest inhibition activity against 4 pathogenic fungi. The strain was, therefore, selected as a biocontrol candidate for both the pathogens and its bacteriological characteristics and 165 rDNA sequences were analyzed. Phenotypic and biochemical characteristics of the selected Rsm220 were highly related to the type strain of S. marcescens and 165 rDNA sequencing of Rsm220 showed a homology of 98.2％ to the type strain of S. marcescens. The strain Rsm220 was identified as S. marcescens and the inhibition result of this endophytic strain indicates that it is a potential biocontrol agent for R. solani and R grisea.

• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.87-91
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• 1996

The optimum temperature and pH for the enzyme activity were 45$^{\circ}C$ and 10.0, respectively. The enzyme was stable in a pH range of 5 to 10, and 62% of its activity was lost on heat treatment of 60$^{\circ}C$ for 20 min. The activity of the purified enzyme was inhibited by $Fe^{2+},\;Zn^{2+}\;and\;Pb^{2+}$, and slightly activated by $Mn^{2+}\;and\;Ca^{2+}$. ${\gamma}$-Chloromercuribenzoic acid, 2,4-dinitrophenol and $H_{2}O_{2}$ did not show inhibitroy effect on the lipolytic activity of the alkaline lipase but ethylenediaminetetraacetic acid inhibited the enzyem activity. This suggested that the enzyme have metal group in its active site. Sodium salts of bile acids stimulated the enzyme activity. Analysis of hydrolyzates of olive oil after the reaction revealed that Serratia liquefaciens AL-11 produced non-specific lipolytic enzyme.

• Journal of Microbiology and Biotechnology
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• v.18 no.1
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• pp.67-73
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• 2008

The potential of the exopolysaccharide (EPS) from a Serratia sp. strain Gsm01 as an antiviral agent against a yellow strain of Cucumber mosaic virus (CMV-Y) was evaluated in tobacco plants (Nicotiana tabacum cv. Xanthi-nc). The spray treatment of plants using an EPS preparation, 72h before CMV-Y inoculation, protected them against symptom appearance. Fifteen days after challenge inoculation with CMV-Y, 33.33% of plants showed mosaic symptoms in EPS-treated plants compared with 100% in the control plants. The EPS-treated plants, which showed mosaic symptoms, appeared three days later than the controls. The enzyme-linked immunosorbent assay (ELISA) and reverse transcriptase polymerase chain reaction (RT-PCR) analyses of the leaves of the protected plants revealed that the EPS treatment affected virus accumulation in those plants. Analysis of phenylalanine ammonia lyase, peroxidase, and phenols in protected plants revealed enhanced accumulation of these substances. The pathogenesis-related (PR) genes expression represented by PR-lb was increased in EPS-treated plants. This is the first report of a systemic induction of protection triggered by EPS produced by Serratia sp. against CMV-Y.

• The Journal of the Korean Society for Microbiology
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• v.13 no.1
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• pp.25-30
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• 1978

Among clincal isolates, most strains of Serratia marcescens were belonged to nonpigmented form, and several attempts were undertaken for the rapid and simple identification of these strains. Prodigiosin production of non-pigmented strains was uniformly negative in many kinds of solid media as well as in nutrient agar added with various amino acids and thiamine. On blood agar, colonies of S. marcescens turned gradually to grey or dark color by the lapse of incubation period and this characteristic seems to be able to utilize as an indicator for a primary isolation, and also generally paralleled with the results of dehydration of Tween 80 and lipase activity in soy bean oil medium although these reactions were by no means specific to S. marcescens. In order to rule out these non-specific reactions, other tests such as oxidase and sucrose fermentation are required for the final confirmation of this species.

• Korean Journal of Microbiology
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• v.30 no.2
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• pp.71-77
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• 1992

A 50 KD metalloprotease of Serratia marcesrens ATCC 21074 was purified by ammoniumsulfate precipitation. DEAE-cellulose ion exchange chromatography, and sephadex ti-100gel filtration. Optimal pH and temperature of enzyme were pH 8.0 and 37"C, respectively.This enzyme was stable in the ranges of 10-37$^{\circ}$C and pH 5.0--11.0. Thermal denaturationwas investigated by differential scanning calorimetry. Onset temperature of denaturationand endothermic peak temperature were 376$^{\circ}$C and 43.2"C. re:,pectively. The denaturationenthalpy was -8.4mJimg. The purified metalloprotease was ri.sistant to autodigestion for24 hr at 30$^{\circ}$C. Metalloprotease in culture supernatant was also resistant to autodigestionin this conditions. Heat-denatured enzyme. however. was rapidly digested by the nativeenzyme. The metalloprotease was stable to proteolytic digestion by mammalian proteasessuch as trypsin. a-chymotrypsin, and elastase. But the enzyme was easily digested bybacterial protease. thermolysin.bacterial protease. thermolysin.