• The Korean Journal of Zoology
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• v.36 no.1
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• pp.123-132
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• 1993

곤충의 탈피작용에서 일어나는 키틴 분해대사를 구명하기 위한 목적으로 배추흰나비 (Pieris rupae L.)에서 3종의 서N-acetylglucosaminldase(El, Ell, Elll)를 분리, 정제하였다. Polvacrylamide gel 상에서 이들 효소의 활성은 기질과 triphenvltetrazolium chloride와의 반응 결과 생기는 발색정도로 확인하였다. 각각의 분자량은 76,000, 55,000, 35,000 da, pl 값은 모두 5.8이었으며 후p$\beta$GlcNAc와 각p$\beta$GaINAc에 대해서 다같이 기질특이성을 나타내었다. 또한 El과 Elll는 탈피 시기와 일치하는 전용 말기에 최대 활성을 나타내었으며 Ell는 용화 직후에 최대 활성을 나타내었다.

• Journal of Sericultural and Entomological Science
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• v.41 no.3
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• pp.147-153
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• 1999

Chitinolytic enzymes such as ${\beta}$-N-acetylglucosaminidase are major hydrolases involved in insect molting. We have isolated, sequenced a CDNA encoding ${\beta}$-N-acetylglucosaminidase from the silkworm, Bombyx mandarina, and compared its sequence with genes encoding chitinolytic enyzmes from other sources. The insert DNA in the clone is 3,284 nucleotides long with an open reading frame of 1,788 nucleotides that encodes a protein of 596 amino acids with a molecular weight of 68.2 kDa. There is a 3’-untranslated region composed with 1.479 nucleotides and are several potential polyadenylation signals. The predicted amino acid sequence apparently contains a leader peptide of 23 amino acids. A search of the amino acids sequence databases for sequences similarities to other ${\beta}$-N-acetylglucosaminidases or ${\beta}$-N-acetylhexosaminidases. The highest similarity matched with the enzyme from B. mori, which has a sequence identity of 95%. On the other hand, the identity between the B. mandarina enzyme and those from M. sexta and human are 70% and 24%, respectively.

• Journal of Life Science
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• v.9 no.4
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• pp.341-347
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• 1999

Insects use chitinolytic enzyme to digest chitin in the exoskelton during the molting process. We have isolated and sequenced a chitinase-encoding cDNA from the silkworm, Bombyx mandarina, compared its sequenced with genes encoding chitinolytic enzymes from other sources. The insert DNA in the clone is 2,675 nucleotides long with an open reading frame of 1,695 uncletides that encodes a protein of 565 amino acids with a molecuar weight of 63.4 kDa. The 3' -untranslated region of 889 nucleotides is AT-rich and contains two putative polyadenylation signals. The N-terminal sequence of the encoded protein contains numerous hydrophobic residues characteristic of a leader peptide. The amino acid alignment revealed that the endo-$\beta$-N-acetylglucosaminidase had 83% and 97% homology with M. sexta and B. mori, respectively. The deduced amino acid had two highly conserved region at the amino acid residues 97-111 and 139-148 that were related to the existing chitinase.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.43-43
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• 2001

This study evaluated the effect of fertilization-promoting peptide (FPP) on fertilizing ability and glycosidase activity in vitro of spermatozoa frozen-thawed in pig, Using chlortetracycline fluorescence analysis, the various glycosidase analyses and the oocyte penetration test, we have obtained evidence that FPP can promote the fertilizing ability and glycosidase activity of frozen-thawed spermatozoa in vitro. When frozen-thawed spermatozoa was washed with different concentrations of FPP, there were significantly (P<0.05) more acrosome-reacted in medium with 100 nM than 0, 50, 200 and 400 nM. The penetration rates were also highest in medium containing with 100 nM FPP (P<0.05). On the other hand, the $\beta$-N-acetylglucosaminidase activity was at least twofold higher than other glycosidase. In same glycosidase, however, there were no difference in medium with different concentrations of FPP In another experiment, spermatozoa preincubated in medium with or without FPP for 0, 1, 2, 3 and 4 h were inseminated with oocytes matured in vitro. The percentages of spermatozoa that reached acrosome reaction were affected by preincubation and were higher in medium with that than without FPP. When oocytes were inseminated with spermatozoa preincubated in medium with and without FPP during the different periods, however, penetration rates were decreased with preincubation periods of spermatozoa. On the other hand, when the sperm-oocyte were cultured for 4, 8, 12, 16, 20 and 24 h, the penetration rates were higher in spermatozoa preincubated with that than without FPP and had a tendency to increase as time of culture periods. However, The activities of $\alpha$-fucosidase, $\alpha$ -mannosidase, $\beta$-galactosidase and N-acetyl- $\beta$-D-glucosaminidase were higher in medium with that than without FPP regardless of periods of sperm preincubation and sperm-oocyte culture. These results suggest that FPP may play a positive role in promoting of sperm function and glycosidase activity in vitro in pig.

• Mycobiology
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• v.50 no.4
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• pp.244-253
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• 2022

Trichoderma fungi have been intensively studied for mycoparasitism, and the latter is closely related to their cell-wall degrading enzymes including chitinase. Here, we studied marine-derived Trichoderma spp., isolated from distinct sources and locations, for chitinolytic and antifungal activity. Based on morphological and phylogenetic analyses, two strains designated GJ-Sp1 and TOP-Co8 (isolated from a marine sponge and a marine alga, respectively) were identified as Trichoderma bissettii. This species has recently been identified as a closely related species to Trichoderma longibrachiatum. The extracellular crude enzymes of GJ-Sp1 and TOP-Co8 showed activities of chitobiosidase and b-N-acetylglucosaminidase (exochitinase) and chitotriosidase (endochitinase). The optimum chitinolytic activity of the crude enzymes was observed at 50 ℃, pH 5.0, 0-0.5% NaCl concentrations, and the activities were stable at temperatures ranging from 10 to 40 ℃ for 2 h. Moreover, the crude enzymes showed inhibitory activity against hyphal growth of two filamentous fungi Aspergillus flavus and Aspergillus niger. To the best of our knowledge, this is the first report of the chitinolytic and antifungal activity of T. bissettii.