Molecular biological studies on degradation of wood by termite and its symbiotic protozoa

白蚁及其共生原生动物降解木材的分子生物学研究

• 批准号: 07306017
• 负责人: AZUMA Jun-ichi
• 金额: $ 8.06万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07306017/
• 关键词: termite; symbiotic protozoa; degradation of wood; symbiosis; cellulase; molecular biology; lignin degradation; 分子生物学的解析

Relationship between termite and hindgut protozoa is a typical model of symbiosis. Exact enzymological clarification of the relationship between termite and hindgut bacteria has not been done, and biochemical problems about functional aspects of each protozoa were not clariffied. During the research works financially supported by this Grant-in-Aid for Scientific Research, biochemical and molecular biological studies on polysaccharide degrading enzymes including cellulases produced both by termite and protozoa have been initiated. The abstract of the results given by this research work is summarized below.1)Three types of cellulases, endoglucanase and beta-glucosidase secreted from termite and cellobiohydrolase secreted from protozoan origin, were isolated from a lower termite, Coptotermes formosanus Shiraki, and their amino acid compositions were analyzed.3)Endoglucanase type ellulases secreted from termite were isolated from a lower termite, Reticulitermes speratus Kolbe, and a higher termite, Nasutitermes takasagoensis (Shiraki), and some of their enzymological properties were characterised. Further, genetic approach of the endoglucanase secreted from Reticulitermes speratus Kolbe was tried to clone of its DNA.3)Genetic research work of a Bacillus thuringiensis which produced a insectiside has been done as a model for genetic research work of cellulases from termite and protozoa.4)Degradation of lignin by lower termite in its hindgut has been evidenced by combination of chemical analysis and CP/MAS solid state NMR.In addition, ingestion of lignin by the middle size protozoa in the hind gut of Coptotermes formosanus Shiraki has been clarified.5)Visualization of secretion of cellulase from Reticulitermes speratus Kolbe has been succeeded by using immunotechnological technique.

白蚁与后肠原虫的关系是典型的共生关系。白蚁和后肠细菌之间的关系还没有做精确的酶学澄清，每个原生动物的功能方面的生化问题没有澄清。在这项科学研究补助金资助的研究工作期间，已开始对白蚁和原生动物产生的多糖降解酶，包括纤维素酶进行生物化学和分子生物学研究。本研究的主要结果如下：1）从台湾乳白蚁（Coptotermes formosanus Shiraki）中分离到三种纤维素酶，即白蚁分泌的内切葡聚糖酶和β-葡萄糖苷酶以及原生动物分泌的纤维二糖水解酶，并对其氨基酸组成进行了分析; 3）从散白蚁（Reticulitermes speratus Kolbe）中分离到白蚁分泌的内切葡聚糖酶型纤维素酶，和一种高等白蚁Nasutitermes takasagoensis（Shiraki），并对其酶学性质进行了研究。3）对苏云金芽孢杆菌（Bacillus thuringiensis）进行了遗传学研究，并将其作为白蚁和原生动物纤维素酶遗传学研究的模型。4）化学分析和CP/MAS固体NMR相结合，证实了低等白蚁后肠对木质素的降解。5）利用免疫技术成功地观察到黄胸散白蚁（ReticulitermessperatusKolbe）分泌纤维素酶。

项目成果

Yoshisue, H.: "Cloning and characterization of a Bicillus thruningiensis homolog of the spoIIID gene from Bacillus subtilis" Gene. 154. 23-29 (1995)

Yoshisue, H.：“来自枯草芽孢杆菌的 spoIIID 基因的苏宁芽孢杆菌同源物的克隆和表征”基因。

Y.Yoshimura: "Degradation of wood in the digestive tract of a higher termite,Nsutitermes takasagoensis(Shiraki)(Isoptea : Termididae)" Mokuzai Gakkaishi. 42. 1250-1257 (1996)

Y.Yoshimura：“高等白蚁 Nsutitermes takasagoensis（Shiraki）（Isoptea：Termididae）消化道中木材的降解”Mokuzai Gakkaishi。

Nishino, T.: "Elastic modulus of the crystalline regions of cellulose triesters" J. Polym. Sci. : Part B. 33. 611-168 (1995)

Nishino, T.：“纤维素三酯结晶区域的弹性模量”J. Polym。

T.Iwata: "Molecular and crystal structure of cellulose propanoate diacetate(CPDA,2,3-di-O-acetyl-6-O-propanoyl cellulose)" Cellulose. 3. 91-106 (1996)

T.Iwata：“纤维素丙酸酯二乙酸酯（CPDA，2,3-二-O-乙酰基-6-O-丙酰纤维素）的分子和晶体结构”纤维素。

Inoue, T., K.Murashima, J.I.Azuma, A.Sugimoto and M.Slaytor: "Cellulose and xylan utilization in the lower termite Reticulitermes speratus" Journal of Insect Physiology. 43(3). 235-242 (1997)

Inoue, T.、K.Murashima、J.I.Azuma、A.Sugimoto 和 M.Slaytor：“低等白蚁散白蚁中的纤维素和木聚糖利用”昆虫生理学杂志。