CHITINOLYTIC ACTIVITIES IN HELIGMOSOMOIDES-POLYGYRUS AND THEIR ROLE IN EGG HATCHING
CHITINOLYTIC ACTIVITIES IN HELIGMOSOMOIDES-POLYGYRUS AND THEIR ROLE IN EGG HATCHING
复制标题
DOI：
10.1016/0166-6851(93)90054-2
复制
发表时间：
1993-04-01
影响因子：
1.5
通讯作者：
GOODAY, GW
中科院分区：
文献类型：
--
作者：
ARNOLD, K;BRYDON, LJ;GOODAY, GW
用组织化学和生化技术测定了多回Heligmosomoides polygyrus蛋壳中几丁质的含量。几丁质约占鸡蛋干重的5%。用钙白染色发现，在蛋壳孵化或破裂后，染色剂更容易接触到蛋壳中的甲壳素。利用荧光底物在成年雄性（低水平）、雌性和卵的提取物中检测到几丁质水解活性。用相同的底物观察发育中的幼虫体内的酶活性。在幼虫的后三分之一处，它分布在直径约为1微米的离散颗粒中，在直径约为5微米的区域中成群出现。几丁质溶解活性随卵龄增加而增加，并在卵孵化后释放到培养基中。几丁质酶活性对特异性几丁质酶抑制剂异胺嘧啶（allosamidin）的抑制非常敏感，对2.2 nM的鸡蛋粗提物的IC50值最高。然而，用250 muM allosamidin处理鸡蛋导致鸡蛋孵化减慢而不是停止。
The occurrence of chitin in the eggshell of Heligmosomoides polygyrus has been determined by histochemical and biochemical techniques. Approximately 5% of the egg dry weight was chitin. Staining with Calcofluor white showed the chitin in the eggshell to be more accessible to the stain after hatching or rupturing of the eggshell. Chitinolytic activity has been detected using fluoroscent substrates in extracts of adult males (at low levels), females and eggs. Enzyme activity in situ, within the developing larvae, was visualised with the same substrates. It was localized in discrete granules about 1 mum in diameter which occurred as groups in areas of about 5 mum in diameter, in the posterior third of the larvae. The chitinolytic activity in the eggs increased with the age of the egg and was released into the medium when the eggs hatched. The chitinase activities were very sensitive to inhibition by allosamidin, a specific chitinase inhibitor, with an IC50 for the crude egg extract of 2.2 nM. However, treatment of eggs with 250 muM allosamidin resulted in a slowing but not cessation of egg hatching.