• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1998.06a
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• pp.350.1-351
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• 1998

• Journal of Life Science
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• v.25 no.2
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• pp.121-129
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• 2015

Alginates are found in marine brown seaweeds and in extracellular biofilms secreted by some bacteria. Previously, we reported an oligoalginate lyase from Sphingomonas sp. MJ-3 (MJ3-Oal) that had an exolytic activity and protein sequence homology with endolytic polymannuronate (polyM) lyase in the N-terminal region. In this study, the MJ3-Oal was tested for both exolytic and endolytic activity by homology modeling using the crystal structure of Alg17c from Saccharophagus degradans 2-40T. The tyrosine residue at the $426^{th}$ position, which possibly formed a hydrogen bond with the substrate, was mutated to phenylalanine. The FPLC profiles showed that MJ3-Oal degraded alginate quickly to monomers as a final product through the oligmers, whereas the Tyr426Phe mutant showed only exolytic alginate lyase activity. $^1H$-NMR spectra also showed that MJ3-Oal degraded the endoglycosidic bond of polyM and polyMG (polymannuronate-guluronate) blocks. These results indicate that oligoalginate lyase from Sphingomonas sp. MJ-3 probably catalyzes the degradation of both exo- and endo-glycosidic bonds of alginate.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.161-163
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• 2018

The genome of Flavivirga eckloniae $ECD14^T$ isolated from a seaweed Ecklonia cava was sequenced. The genome comprises a single circular 5,665,358 bp chromosome with a G + C content of 33.9%, 4,647 total genes, 4,595 protein-coding genes, 44 pseudo genes, and 52 RNA genes. CRISPER genes and sequences were not found and there were some phage remnants and transposons. This strain contains alginate lyase and ${\beta}$-glucosidase genes responsible for the degradation of seaweed polysaccharides.

• Korean Journal of Microbiology
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• v.51 no.4
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• pp.364-373
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• 2015

As an effort to utilize alginate, 103 bacterial isolates that were positive for the alginate lyase activity were isolated from various clams and seawater samples collected in Incheon coastal area. Among them, 3 strains (M1-2-1, M6-1, and C8-15) were finally selected for further analysis based on their activities at higher levels than others. These isolates were all Gram-negative and rod shaped halophilic bacteria with motility. According to their physiological and biochemical properties as well as DNA sequence of their 16S rRNA genes, M1-2-1 and M6-1 were identified as a member of genus Pseudoalteromonas and C8-15 belonged to genus Vibrio. They exhibited the alginate degrading activity at the maximal level when they were cultured in APY broth for 6-8 h at $25^{\circ}C$. Both their growth and the enzyme activity were greatly enhanced when NaCl was added to the growth medium. The crude alginate lyases from the supernatants of the bacterial cultures showed the highest activity at $45^{\circ}C$ and pH 7.0-8.0. M1-2-1 and M6-1 produced 2.723 and 1.976 g/L of reducing sugar from alginate, respectively, suggesting that they have potential for commercial application.

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.66.1-66.1
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• 2007

See Full Text

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.146-151
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• 1996

For the purpose of production of oligosaccharides from alginates, a bacterium was isolated from seaweed, and then an enzyme which degraded alginates was obtained from the bacterium. A specific activity of the enzyme was shown in G-rich block and Na-alginate (Wako Co.) as a result of reaction between the enzyme and six types of alginates (G-rich block, M-rich block and 4 commercial Na-alginate). Degradation products were prepared from the Na-alginate (Wako Co.) by the enzyme. The oligosaccharides were fractioned by Sephadex G-25 and Bio-gel P-2 and identified on a thin layer chromatography (TLC). Degree of polymerization (DP) of the oligosaccharides was shown from 2.6 to 7.5.

• KSBB Journal
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• v.24 no.5
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• pp.483-488
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• 2009

The Brown-algae polysaccharide consisting of alginate and laminaran is usable as high bio-ethanol production if hydrolyzed to monomer unit. The objective of this study is to produce bio-ethanol from brown-algae using enzymatic saccharification. Bio-ethanol was produced by Saccharomyces cerevisiae KCCM 1129 and Pachysolen tannophilus KCTC 7937 strains. The substrate used Laminaria japonica, Sargassum fulvellum and Hizikia fusiformis. We isolated a new alginate lyase and laminaran lyase producing microorganism for hydrolysis of brown-algae from southern sea of Gijang. The reducing sugar was obtained 1.90 g/L from Laminarin japonica 20 g/L that used enzyme from Bacterium antarctica. In pretreatment of the most suitable brown-algae for ethanol production, ethanol concentration of 0.93 g/L and yield of 4.65% were obtained in condition of Laminaria japonica in medium.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.486-486
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• 2005

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1481-1487
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• 2016

Lactic acid bacteria showing alginate-degrading and cellulolytic activity were isolated and identified as a starter for seaweed fermentation. A total of 331 strains of lactic acid bacteria isolated from various Korean traditional foods, such as Kimchi, Jeotgal, and Makgeolli, were examined alginate-degrading and cellulolytic activity by the plate assay method. Six strains showed strong alginate-degrading and cellulolytic activity among the isolated 331 strains. Among these six strains, four strains (strain No. 162, 164, 192, and 196) showed probiotic properties (antimicrobial activity, tolerance to simulated gastric juice, artificial bile acid, and NaCl). No. 192 strain (Gram-positive cocci, catalase negative, and homofermentative) showed the best probiotic properties among selected strains and was identified as Enterococcus faecium by 16S rRNA sequencing. Strain No. 192 (E. faecium) showed the best growth and antioxidative activity during seaweed (sea mustard and sea tangle) fermentation for 72 h at $37^{\circ}C$ among the four selected strains.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.299-301
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• 2018

Microbulbifer agarilyticus GP101 was isolated from the gut of a marine invertebrate Turbo cornutus and capable of degrading polysaccharide such as agar, alginate, and ${\kappa}$-carrageenan constituting algal cell wall. To obtain genomic basis of polysaccharide-degrading activity, we sequenced genome of strain GP101. The genome consists of 4,255,625 bp, 3,458 coding sequences with 55.4% G + C contents. BLASTP search revealed the presence of seven agarases, five alginate lyases, ten glucanases, four chitinases, two xylanases, one ${\kappa}$-carrageenase, and one laminarinase. The genomic data of strain GP101 will provide potential uses in the bioconversion process of diverse polysaccharide into bioenergy and biochemicals.