Sakai K, Yamauchi T, Nakasu F, Ohe T
Department of Biochemistry, Osaka Municipal Technical Research Institute, Japan.
Biosci Biotechnol Biochem. 1996 Oct;60(10):1617-22. doi: 10.1271/bbb.60.1617.
Bacteria capable of assimilating cellulose acetate, strains SB and SC, were isolated from soil on a medium containing cellulose acetate as a carbon source, and identified as Neisseria sicca. Both strains degraded cellulose acetate membrane filters (degree of substitution, DS, mixture of 2.8 and 2.0) and textiles (DS, 2.34) in a medium containing cellulose acetate (DS, 2.34) or its oligomer, but were not able to degrade these materials in a medium containing cellobiose octaacetate. Biodegradation of cellulose acetate (DS, 1.81 and 2.34) on the basis of biochemical oxygen demand reached 51 and 40% in the culture of N. sicca SB and 60 and 45% in the culture of N. sicca SC within 20 days. A decrease in the acetyl content of degraded cellulose acetate films and powder was confirmed by infrared and nuclear magnetic resonance analyses. After 10-day cultivation of N. sicca SB and SC, the number-average molecular weight of residual cellulose acetate decreased by 9 and 5%, respectively. Activities of enzymes that released acetic acid and produced reducing sugars from cellulose acetate were mainly present in the culture supernatant. Reactivity of enzymes for cellulose acetate (DS, 1.81) was higher than that for cellulose acetate (DS, 2.34).
能够同化醋酸纤维素的细菌，SB和SC菌株，是从以醋酸纤维素作为碳源的培养基中的土壤中分离出来的，并被鉴定为干燥奈瑟菌。这两种菌株在含有醋酸纤维素（取代度，DS，2.34）或其低聚物的培养基中能降解醋酸纤维素膜过滤器（取代度，DS，2.8和2.0的混合物）和纺织品（DS，2.34），但在含有八乙酸纤维二糖的培养基中不能降解这些材料。基于生化需氧量，在20天内，干燥奈瑟菌SB培养物中醋酸纤维素（DS，1.81和2.34）的生物降解率达到51%和40%，干燥奈瑟菌SC培养物中达到60%和45%。通过红外和核磁共振分析证实了降解的醋酸纤维素薄膜和粉末中乙酰含量的降低。干燥奈瑟菌SB和SC培养10天后，残留醋酸纤维素的数均分子量分别降低了9%和5%。从醋酸纤维素释放乙酸并产生还原糖的酶活性主要存在于培养上清液中。酶对醋酸纤维素（DS，1.81）的反应性高于对醋酸纤维素（DS，2.34）的反应性。
