Abstract
The intestinal microflora of humans is an extraordinarily complex mixture of microorganisms, the majority of which are anaerobic bacteria. Amongst them, most prevalent bacteria are Bacteroides, Eubacterium, Peptococcus, Bifidobacteria. We isolated a Bacteroides fragilis strain from a Korean adult and examined various glycosidase activities of this strain. The activities of $N-acetyl-{\beta}-glucosaminidase,\;{\alpha}-fucosidase$, ${\beta}-glucuronidase$, chitobiase and PNPCase were stronger in Bacteroides fragilis Roid 8 than in other intestinal anaerobic bacteria. $N-acetyl-{\beta}-glucosaminidase$ was strongest, followed by ${\alpha}-fucosidase$, ${\beta}-glucuronidase$ and PNPCase. The activities of ${\beta}-galactosidase$, ${\beta}-xylosidase,\;{\alpha}-arabinofuranosidase$ were not present or very low. The activities of ${\alpha}-glucosidase$, ${\beta}-glucosidase$ and ${\alpha}-galactosidase$ were present but at a lower level than in Bifidobacterium. The effect of the carbon sources on the production of $N-acetyl-{\beta}-glucosaminidase$, ${\alpha}-fucosidase$, ${\beta}-glucuronidase$ and PNPCase of Bacteroides fragilis Roid 8 was investigated. :.actose and glucose lowered the production of the varous glycosidase enzymes studied in this work. In addition, we investigated the optimum temperature and pH of each glycosidase from Bacteroides fragilis Roid-8 using crude enzyme preparations.
인체의 대장은 여러 종류의 균들에 의하여 상재균총이 이루어져 있는데 이들중 혐기성 균들이 주종을 이루고 있다. 이들 혐기성 균들 중 가장 많은 수가 Bacteroides이다. 본 연구에서 한국인으로부터 분리된 Bacteroides fragilis Roid 8은 장내의 다른 혐기성 균주들에 비하여 $N-acetyl-{\beta}-glucosaminidase$, ${\alpha}-fucosidase$, ${\beta}glucuronidase$ chitobiase, PNPCase 등의 활성이 높았다. ${\beta}-galactosidase$, ${\beta}-xylosidase$, ${\alpha}-arabinofuranosidae$활성은 없었고 ${\alpha}-glucosidase$, ${\beta}-glucosidase$, ${\alpha}-galactosidae$ 등의 생산은 Bifidobacteria 에 비하여 낮았다. BHI 기본배지에 여러 종류의 탄수화물을 첨가하여 배양한 뒤 생산된 $N-acetyl-{\beta}-glucosaminidae$, ${\alpha}-fucosidase$, ${\beta}-glucuronidase$ chitobiase, PNPCase, ${\beta}-glucosidase$, ${\beta}-glucosidase$ ${\alpha}-galactosidase$ 활성을 조사한 결과 모두 glucose와 lactose 첨가배지에서 이들 효소들의 활성이 낮았다. 조사된 모든 효소들에 대하여 특이적으로 현저히 생산을 증가시키는 당은 없었다. 이들 8개의 효소에 대하여 최적 pH와 최적온도가 조사되었다.