• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.616-623
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• 2008

In spite of an increasing interest in fucoidans as biologically active compounds, no convenient commercial sources with fucoidanase activity are yet available. A marine bacterial strain that showed confluent growth on a minimal medium containing fucoidan, prepared from Korean Undaria pinnatifida sporophylls, as the sole carbon source was isolated and identified based on a 16S rDNA sequence analysis as a strain of Sphingomonas paucimobilis, and named Sphingomonas paucimobilis PF-1. The strain depolymerized fucoidan into more than 7 distinct low-molecular-mass fucose-containing oligosaccharides, ranging from 305 to 3,749 Da. The enzyme activity was shown to be associated with the whole cell, suggesting the possibility of a surface display of the enzyme. However, a whole-cell enzyme preparation neither released the monomer L-fucose from the fucoidan nor hydrolyzed the chromogenic substrate p-nitrophenyl-${\alpha}$-L-fucoside, indicating that the enzyme may be an endo-acting fucoidanase rather than an ${\alpha}$-L-fucosidase. Therefore, this would appear to be the first report on fucoidanolytic activity by a Sphingomonas species and also the first report on the enzymatic degradation of the Korean Undaria pinnatifida sporophyll fucoidan. Moreover, this enzyme activity may be very useful for structural analyses of fucose-containing polysaccharides and the production of bioactive fucooligosaccharides.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.25-25
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• 2003

본 연구는 돼지 동결-융해 정자의 배양에 의한 체외수정능력과 glycosidase activity의 관계를 검토하였으며, 또한 돼지난자의 투명대내에서 발견된 당잔기에 대한 정자의 glycosidase 특이성을 확인하기 위하여 $\alpha$-L-fucosidase, $\alpha$-D-mannosidase, $\beta$-D-galactosidase 및 N-acetyl-$\beta$-D-glucosaminidase ($\beta$-GlcNAc'ase)의 activity를 분석하였다. 그 결과 glycosidase activity는 동결정자의 융해 후 배양하지 않았을 때보다 2시간 배양했을 때 더 높게 나타났다. $\beta$-GlcNAc'ase의 activity는 정자 배양 유무에 관계없이 다른 glycosidase 처리시보다 최소한 2배 이상 높게 나타났다. 또한 첨체반응이 유기된 정자의 비율은 glycosidase ($\alpha$-D-mannosidase; P<0.05)에 의해 영향을 받았으며 정자를 배양하지 않은 경우보다는 배양된 정자에서 높게 나타났다. 그러나 배양시간에 따른 정자의 생존성에 대해 glycosidase의 종류에 따른 유의차는 인정되지 않았다. 한편 투명대내 정자의 접착과 침입에 대한 또 다른 실험에서, 서로 다른 glycosidase가 첨가된 배양액내에서 수정된 정자가 배양시간이 길어짐에 따라 정자의 침입율은 낮아졌다($\beta$-GlcNAc'ase; P<0.05). 투명대내의 정자접착 정도는 glycosidase의 첨가시에 무첨가시보다 접착정도가 더 높았으며, 가장 높은 접착율은 $\beta$-GlcNAc'ase첨가시 나타났다. 또한 모든 glycosidase 처리시 2시간 배양한 정자보다는 배양하지 않은 정자에서 투명대에 대한 접착정도가 높게 나타났으며, $\alpha$-D-mannosidase의 처리시 유의적인 차이를 보였다(P<0.05). 본 연구의 결과, $\beta$-GlcNAc'ase가 주로 돼지정자의 원형질막내에 존재하는 것으로 추측되며, 배양된 정자에 의한 투명대 접착정도와 침입율이 낮았음에도 불구하고 glycosidase activity가 증가하는 것으로 나타났다

• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.591-597
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• 2017

Maribacter dokdonensis DSW-8 was isolated from the seawater off Dokdo in Korea. To investigate the genomic features of this marine bacterium, we sequenced its genome and analyzed the genomic features. After de novo assembly and gene prediction, 16 contigs totaling 4,434,543 bp (35.95% G+C content) in size were generated and 3,835 protein-coding sequences, 36 transfer RNAs, and 6 ribosomal RNAs were detected. In the genome of DSW-8, genes encoding the proteins associated with gliding motility, molybdenum cofactor biosynthesis, and utilization of several kinds of carbohydrates were identified. To analyze the genomic relationships among Maribacter species, we compared publically available Maribacter genomes, including that of M. dokdonensis DSW-8. A phylogenomic tree based on 1,772 genes conserved among the eight Maribacter strains showed that Maribacter speices isolated from seawater are distinguishable from species originating from algal blooms. Comparison of the gene contents using COG and subsystem databases demonstrated that the relative abundance of genes involved in carbohydrate metabolism are higher in seawater-originating strains than those of algal blooms. These results indicate that the genomic information of Maribacter species reflects the characteristics of their habitats and provides useful information for carbon utilization of marine flavobacteria.

• Korean Journal of Animal Reproduction
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• v.27 no.2
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• pp.153-161
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• 2003

This study has evaluated effect of the spermatozoa incubation on the glycosidase activity and fertilizing ability in vitro in the pig. To identify sperm glycosidases specific for sugar residues found in the zona pellucida of pig oocytes, the spermatozoa were treated experimentally and assayed for activities of $\alpha$-L-fucosidase, $\alpha$-D-mannosidase, $\beta$-D-galactosidase and N-acetyl-$\beta$-D-glucosaminidase ($\beta$-GlcNAc'ase). The glycosidases activity were higher in spermatozoa incubated for 2h than without incubation. The $\beta$-GlcNAc'ase activity was at least two-fold higher than other glycosidase regardless of spermatozoa incubation. In the same glycosidases, the activity had a tendency to increase as time of spermatozoa incubation was prolonged, but there were no differences in spermatozoa incubated during the various periods (4~24h). The percentages of spermatozoa that reached acrosome reaction were affected by glycosidases in the medium (P<0.05, for mannosidase), and were higher in spermatozoa with that than without incubation. On the other hand, the spermatozoa motility were decreased with incubation periods, but no effects by different glycosidases on the change of sperm motility during the various periods of incubation. In other experiment, the binding and penetration of pig spermatozoa were tested with oocytes matured in vitro in the presence of various glycosidase. The penetration rates were decreased with incubation of spermatozoa when oocytes were inseminated in medium with different glycosidases. These rates were higher in spermatozoa non-incubated than with incubation for 2h (P<0.05 for GlcNAc'ase; P<0.01 for control group). The sperm-zona binding rate in control group were higherthan in medium with glycosidases. In addition, the highest binding rate were obtained in medium with GlcNAc'ase. In all glycosidases, the sperm-zona binding rate in spermatozoa without incubation were higher than incubation for 2h. The significant differences were obtained in spermatozoa treated with $\alpha$-D-mannosidase (P<0.05). These results suggest that $\beta$-GlcNAc'ase is present mainly in the plasma membrane of pig spermatozoa. It was also shown that the glycosidase activity were increased in all glycosidases in spite of low sperm-zona binding rate and penetration rates by spermatozoa incubation.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1725-1731
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• 2002

The distribution and activities of hydrolytic enzymes (cellulolyti, hemicellulolytic,pectinolytic and others) in the rumen compartments of Hereford bulls fed 100% alfalfa hay based diets were evaluated. The alfalfa proportion in the diet was gradually increased for two weeks. Whole rumen contents were processed into four fractions: Rumen contents including both the liquid and solid fractions were homogenized and centrifuged, and the supernatant was assayed for enzymes located in whole rumen contents (WRE); rumen contents were centrifuged and the supernatant was assayed for enzymes located in rumen fluids (RFE); feed particles in rumen contents were separated manually, washed with buffer, resuspended in an equal volume of buffer, homogenized and centrifuged and supernatant was assayed for enzymes associated with feed particles (FAE); and rumen microbial cell fraction was separated by centrifugation, suspended in an equal volume of buffer, sonicated and centrifuged, and the supernatant was assayed for enzymes bound with microbial cells (CBE). It was found that polysaccharide-degrading proteins such as $\beta$-1,4-D-endoglucanase, $\beta$-1,4-D-exoglucanase, xylanase and pectinase enzymes were located mainly with the cell bound (CBE) fraction. However, $\beta$-D-glucosidase, $\beta$-D-fucosidase, acetylesterase, and $\alpha$-L-arabinofuranosidase were located in the rumen fluids (RFE) fraction. Protease activity distributions were 37.7, 22.1 and 40.2%, and amylase activity distributions were 51.6, 18.2 and 30.2% for the RFE, FAE and CBE fractions, respectively. These results indicated that protease is located mainly in rumen fluid and with microbial cells, whereas amylase was located mainly in the rumen fluid.