TKUPSP017 濃度於0.05% (w/v) 時的抑制率達100%,抑制效果會隨
CHS 與TKUPSP017 預反應時間的增長而有所提升。此外,抑制劑結構對於
CHS 酵素活性的影響,以及添加TKUPSP017 於培養基對於B. cereus
TKU030 生長之影響亦有探討。CHS 被抑制不會影響TKU030 的生長,隨著
TKUPSP017 濃度提高,TKU030 生長狀況反而越好。 The chitosanase, chitinase and proease-producing strain
TKU030 was isolated from soil in Tamkang University with squid pen powder as the sole carbon/nitrogen source and identified as Bacillus cereus. A chitosanase (CHS) was purified from the culture supernatant by ammonium sulfate precipitation, Sephacryl S-100 gel chromatography, DEAE- Sepharose column chromatography and Sephacryl S-100 rechromatography . The molecular mass of CHS determined by SDS-PAGE was approximately 43 kDa. The optimum temperature, optimum pH, thermal stability, and pH stability of CHS were 40oC, pH 4, 30-40oC and pH 3-7, respectively.The activity of CHS was inhibited by Mn2+, Cu2+, Fe2+ and a boron-containing compound of TKUPSP017.
The inhibition of CHS activity reached 100% at 0.05% (w/v) of TKUPSP017. The inhibitory activity increased with the
preincubating time of TKUPSP017 and CHS. The effects of
inhibitor structures on enzyme activity and growth of strain TKU030 in media supplemented with TKUPSP017 were also studied.Growth of strain TKU030 was not influenced by inhibiting CHS activity but enhanced by increasing TKUPSP017 concentration.