• Biomolecules & Therapeutics
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• v.16 no.4
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• pp.356-363
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• 2008

A bacterial strain with good antibacterial activities against Staphylococus aureus and Escherichia coli was isolated from a marine sponge Stelleta sp., and it was identified as a Psychrobacter sp. by comparative 16S rDNA sequence analysis. In our search for bioactive secondary metabolites from this psychrophillic and halotolerent bacterium, sixteen cyclic dipeptides (1-16) were isolated and their structures were identified on the basis of NMR analysis. In the test of the compounds for the protective effect against Vibrio vulnificusinduced cytotoxicity in human intestinal epithelial cells, cyclo-(L-Pro-L-Phe) (5) exhibited significant protective effect. Compounds 2, 6, and 11, which contain D-amino acid, were first isolated from bacteria.

• Korean Journal of Microbiology
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• v.46 no.3
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• pp.255-261
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• 2010

The bacterial community structure associated with two marine sponges, Hyrtios sp. 604 and Callyspongia sp. 612 collected from the South Pacific Ocean were analyzed by 16S rDNA-denaturing gradient gel electrophoresis (DGGE). The phylogenetic analysis showed that the bacterial community associated with Hyrtios sp. 604 contained diverse bacterial groups such as Chloroflexi, Firmicutes, Cyanobacteria, Alphaproteobacteria, Gammaproteobacteria, Actinobacteria, and Acidobacteria. Callyspongia sp. 612 harbored Chloroflexi, Cyanobacteria, Alphaproteobacteria, and Gammaproteobacteria. Hyrtios sp. 604 belonging to genus Hyrtios known to produce natural products showed greater bacterial diversity than Callyspongia sp. 612. Phylum Actinobacteria was shown to be one of dominant bacterial groups in Hyrtios sp. 604. Although the same phyla of bacteria were found in both sponge species, the spongeassociated predominant bacterial groups differed between the two sponges with different chemical characteristics from the same geographical location. Uncultured bacteria represented over 90% of the bacteria diversity present in all bacterial communities of the sponges.

• Korean Journal of Microbiology
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• v.51 no.4
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• pp.398-406
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• 2015

Culture-dependent ARDRA and culture-independent DGGE were employed to investigate the bacterial community associated with the marine sponge Halichondria panicea collected from Jeju Island. A total of 120 bacterial strains associated with the sponge were cultivated using modified Zobell and Marine agar media. PCR amplicons of the 16S rRNA gene from the bacterial strains were digested with the restriction enzymes HaeIII and MspI, and then assigned into different groups according to their restriction patterns. The 16S rRNA gene sequences derived from ARDRA patterns showed more than 96% similarities compared with known bacterial species, and the isolates belonged to four classes, Alphaproteobacteria, Gammaproteobacteria, Bacteroidetes, and Firmicutes, of which Alphaproteobacteria was dominant. DGGE fingerprinting of 16S rRNA genes amplified from the sponge-derived total gDNA showed 14 DGGE bands, and their sequences showed 100% similarities compared with the sequences available in GenBank. The sequences derived from DGGE bands revealed high similarity with the uncultured bacterial clones. DGGE revealed that bacterial community consisted of seven classes, including Alphaproteobacteria, Gammaproteobacteria, Acidobacteria, Actinobacteira, Bacteroidetes, Cyanobacteria, and Chloroflexi. According to both the ARDRA and DGGE methods, three classes, Alphaproteobacteria, Gammaproteobacteria, and Bacteroidetes, were commonly found in H. panicea. However, overall bacterial community in the sponge differed depending on the analysis methods. Sponge showed more various bacterial community structures in culture independent method than in culture-dependent method.

• Journal of Microbiology and Biotechnology
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• v.19 no.3
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• pp.229-237
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• 2009

Among 12 marine bacterial strains from the China coast that exhibited interesting bioactivity (positive for both antimicrobial and cytotoxic activities), only four strains, namely, NJ6-3-1, NJ6-3-2, NB-6, and YTHM-17, had a KS domain or A domain when screened for PKS and NRPS genes using a PCR. Interestingly, two of these strains belonging to Pseudoalteromonas and associated with the marine sponge Hymeniacidon perleve were positive for both PKS and NRPS, whereas the other two strains of Pseudoalteromonas did not have a PKS or NRPS gene. A molecular phylogeny analysis and DGGE analysis of the Pseudoalteromonas sp. indicated that they had a specific affinity with the host marine sponge Hymeniacidon perleve. Furthermore, an analysis of a partial sequence of Pseudoalteromonas sp. NJ6-3-2 isolated from the marine sponge Hymeniacidon perleve obtained from genomic walking using a computational approach indicated a relatively complete PKS module including auxiliary domains (DH, KR, and Cy).

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.243-251
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• 2006

Dideoxypetrosynol A, a polyacetylene from the marine sponge Petrosia sp., is known to exhibit significant selective cytotoxic activity against a small panel of human tumor cell lines, however, the mechanisms of which are poorly understood. In the present study, it was investigated the further possible mechanisms by which dideoxytetrosynol A exerts its anti-proliferative action in cultured human leukemia cell line U937. We observed that the proliferation-inhibitory effect of dideoxypetrosynol A was due to the induction of G1 arrest of the cell cycle and apoptosis, which effects were associated with up-regulation of cyclin D1 and down-regulation of cyclin E without any change in cyclin-dependent-kinases (Cdks) expression. Dideoxypetrosynol A markedly induced the levels of Cdk inhibitor p16/INK4a expression. Furthermore, down-regulation of phosphorylation of retinoblastoma protein (pRB) by this compound was associated with enhanced binding of pRB and the transcription factor E2F-1. The increase in apoptosis was associated with a dose-dependent up-regulation in pro-apoptotic Bax expression and activation of caspase-3 and caspase-9. Dideoxytetrosynol A decreased the levels of cyclooxygenase (COX)-2 mRNA and protein expression without significant changes in the levels of COX-1, which was correlated with a decrease in prostaglandin E2 (PGE2) synthesis. Furthermore, dideoxytetrosynol A treatment markedly inhibited the activity of telomerase, and the expression of human telomerase reverse transcriptase (hTERT), a main determinant of the telomerase enzymatic activity, was progressively down-regulated by dideoxytetrosynol A treatment in a dose-dependent fashion. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of dideoxytetrosynol A.

• Journal of Marine Bioscience and Biotechnology
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• v.6 no.2
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• pp.76-83
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• 2014

Bacteria associated with marine sponges seemed to be concerned in halogenation/dehalogenation process of natural compounds. In the present study, the effect of hexabromobenzene (HBB) on the community structure of bacteria associated with a marine sponge Axinella sp. from Chuuk State under anaerobic condition was investigated. Regardless of 100 ppm HBB, most of detected microorganisms displayed high similarity with clones reported from coral or sponges. Amongst, Desulfovibrio marinisediminis like clones were dominant. Clones affiliated with Lentisphaerae and Fusibacter paucivorans (Clostridia) were detected at the conditions without HBB but clones affiliated with Vallitalea guaymasensis (Clostridia) increased its proportion with HBB. From these results and previous reports clones affiliated with D. marinisediminis and V. guaymasensis seemed to be concerned in halogenation/dehalogenation process.

• Natural Product Sciences
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• v.20 no.3
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• pp.202-205
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• 2014

Three compounds including 7,7-bis(3-indolyl)-p-cresol (1), cyclo-(S-Pro-R-Leu) (2) and cyclo-(S-Pro-R-Val) (3) were isolated from the strain of Bacillus megaterium LC derived from the marine sponge Haliclona oculata. All the isolated compounds showed antimicrobial activity at MIC values ranging from 0.005 to $5{\mu}g/mL$ against Gram-negative bacteria Vibrio vulnificus and V. parahaemolyticus, gram-positive bacteria Bacillus cereus and Micrococcus luteus, and the dermatophyte Trichophyton mentagrophytes. The results suggested that these compounds might have potential to be developed as agents treating dermatosis and controlling vibriosis in aquaculture.

• 대한치주과학회:학술대회논문집
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• 2004.11a
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• pp.53-53
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• 2004

• Korean Journal of Ecology and Environment
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• v.47 no.spc
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• pp.39-47
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• 2014

Sponge in Lake Baikal is an unique organism. Microorganisms in sponges are assumed as precious resources for bioactive materials. For understanding the bacterial community in Baikalian sponges by cultivation, 92 strains of bacteria were isolated from lake water and 2 species of sponges, Baikalospongia sp. and Lubomirskia sp., Thirty five bacterial strains are isolated from ambient water near the sponge, 27 bacterial strains from Baikalospongia sp., 30 bacterial strains from Lubomirskia sp.. As a result, 78.3% and 57.6% of isolated bacterial strains has amylase and protease activity respectively, while strains with cellulose and lipase activities were 38.0% and 34.8%. By 16S rRNA sequence analysis of selected strains, 13 strains which were isolated from Baikalospongia sp. were belong to Pseudomonas spp.. Whereas, 14 strains which were isolated from Lubomirskia sp. were Pseudomonas spp., Buttiauxella agrestis, Pseudomonas fluorescens, Yersinia ruckeri, Bacillus spp., Paenibacillus spp., Bacillus thuringiensis, Bacillus simplex, Brevibacterium spp., Acinetobacter lwoffii. In culture media, Pseudomonas spp. dominance was supposed that according to allelophathy.

• Journal of Korean Biological Nursing Science
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• v.21 no.1
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• pp.37-45
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• 2019

Purpose: This descriptive research was on hand dermatitis in clinical nurses. Nurses often have a high rate of hand dermatitis with several factors associated with the dermatitis. The factors analyzed in this study included; general characteristics, work-related factors, hand washing, and allergies relate to hand dermatitis. Methods: Data were collected from April to May 2016. The subjects were nurses who had worked 12 months or more in a University Hospital. They voluntarily gave their consent for the research. The Symptombased questionnaires were sent to 220 nurses and 199 responses were returned. Collected data were analyzed using frequency, percentage, mean, standard deviation, ${\chi}^2-test$, and logistic regression analysis using SPSS 23.0. Results: Prevalence of dermatitis in nurses was 48.2%. Nurses who had worked for over three years were twice more likely to suffer hand dermatitis than nurses who had worked for 3 years or less (adjusted odds ratio [adj. OR]= 1.97, p= .036). Nurses who used alcohol sponge swabs more than 20 times per shift were 2.5 times more likely to suffer hand dermatitis as compared to those who used them less times (adj. OR = 2.51, p= .023). Conclusion: Results revealed that about a half of the clinical nurses suffered from hand dermatitis, hence it is crucial to find appropriate interventions for dermatitis prevention. This concern needs to be addressed especially in nurses who have more work experience and use more alcohol sponge swabs.