SLAYTOR M, SUGIMOTO A, AZUMA J -I., MURASHIMA K, INOUE T
Department of Biochemistry, The University of Sydney, Sydney, N.S.W. 2006, Australia
J Insect Physiol. 1997 Mar;43(3):235-242. doi: 10.1016/s0022-1910(96)00097-2.
The distribution of the enzymes of cellulose and xylan metabolism namely endo-beta-1,4-glucanase, beta-glucosidase, endo-beta-1,4-xylanase and beta-xylosidase activities, in Reticulitermes speratus (Kolbe) was measured both in the salivary glands and in the major gut sections and along the length of the gut in freshly collected termites. The majority of the endo-beta-1,4-glucanase activity (77.8%) was found in the salivary glands which also contained 23.9% of the beta-glucosidase activity. At least 70% of the remaining activity was located in the anterior section of the hindgut. A small amount of endo-beta-1,4-xylanase activity (2.4%), but no beta-xylosidase activity, was present in the salivary glands. The majority of these activities were in the anterior section of the hindgut. The RQ of freshly collected termites at 25 degrees C was 1.03+/-0.01. Maintaining termites for 16 days on wood, cellulose and xylan showed that the RQ values of termites fed on wood or xylan were not significantly different from those of freshly collected termites but significantly increased when maintained on cellulose. The RQ of starved termites after 11 days was 0.81+/-0.02. There were three effects on protozoan populations of feeding termites xylan for 20 days. One species, Dinenympha parva was not affected, while five others, Pyrsonympha grandis, Holomastigotes elongatum, Dinenympha rugosa, Dinenympha leidy and Dinenympha porteri survived for 20 days but slowly decreased in numbers. The numbers of P. grandis and D. leidy surviving for 20 days were significantly different from those in starved termites. The third group comprising the two large species, Teratonympha mirabilis and Trichonympha agilis and three small species, Pyrsonympha modesta, Dinenympha exilis and Dinenympha nobilis disappeared within 15 days as in starved termites. It is suggested that protozoa in the first two groups are xylanolytic. Protozoan populations on wood and cellulose diets were not markedly affected. Selective removal of the protozoa by u.v. irradiation led to the loss of xylanolytic activity and a life span comparable to starved termites. Copyright 1997 Elsevier Science Ltd. All rights reserved
在新采集的白蚁中，测定了纤维素和木聚糖代谢酶（即内切-β-1,4-葡聚糖酶、β-葡萄糖苷酶、内切-β-1,4-木聚糖酶和β-木糖苷酶活性）在黑胸散白蚁（Kolbe）唾液腺、主要肠道部分以及沿肠道长度的分布情况。大部分内切-β-1,4-葡聚糖酶活性（77.8%）存在于唾液腺中，唾液腺中还含有23.9%的β-葡萄糖苷酶活性。其余活性至少70%位于后肠前段。唾液腺中存在少量内切-β-1,4-木聚糖酶活性（2.4%），但不存在β-木糖苷酶活性。这些活性大部分位于后肠前段。新采集的白蚁在25℃时的呼吸商为1.03±0.01。让白蚁在木材、纤维素和木聚糖上饲养16天表明，以木材或木聚糖为食的白蚁的呼吸商值与新采集的白蚁无显著差异，但以纤维素饲养时显著增加。饥饿11天后的白蚁的呼吸商为0.81±0.02。给白蚁喂食木聚糖20天对原生动物种群有三种影响。一种物种，小双鞭毛虫未受影响，而其他五种，大双鞭毛虫、细长全鞭毛虫、皱纹双鞭毛虫、莱迪双鞭毛虫和波特双鞭毛虫存活了20天，但数量缓慢减少。存活20天的大双鞭毛虫和莱迪双鞭毛虫的数量与饥饿白蚁中的数量有显著差异。第三组包括两个大型物种，奇异巨鞭毛虫和敏捷披发虫以及三个小型物种，谦逊双鞭毛虫、微小双鞭毛虫和高贵双鞭毛虫在15天内消失，与饥饿白蚁的情况相同。建议前两组中的原生动物具有木聚糖分解能力。以木材和纤维素为食的白蚁的原生动物种群未受到明显影响。通过紫外线照射选择性去除原生动物导致木聚糖分解活性丧失，寿命与饥饿白蚁相当。版权所有1997爱思唯尔科学有限公司。保留所有权利
