分离一株具有强絮凝特性的芽孢杆菌Bacillus sp. F2, 絮凝率达84%, 构建了絮凝基因组文库. 筛选文库获得一株表达絮凝活性的大肠杆菌阳性克隆子FC2, 序列分析得出该克隆序列为新的絮凝基因.红外光谱分析证明FC2的絮凝有效成分与F2一致, 说明FC2絮凝性状遗传于原絮凝菌F2. 依据不同糖对其絮凝水平的抑制, 将克隆菌确定为FLO1型絮凝菌. 并研究了该絮凝型菌株的相关生理、生化特性. 结果表明, FLO1型菌絮凝只受甘露糖抑制,对Ca2+浓度、pH值、温度和放置时间只有一定耐受性.
One strain, named as Bacillus sp. F2, of which flocculent ability can reach 84%, was separated. Flocculent genomic library was constructed.A strain of Bacillus coli. Positive clone FC2, which could express flocculent activity, was acquired after selection. Infrared spectrum analysis demonstrated that FC2’s flocculent characteristic inherited from the original flocculent bacterium F2. The cloning bacterium were divided into FLO1 phenotypes on the basis of their response to sugar inhibition. Related physiological and biochemical characteristics of the strains were studied. The results show that the flocculation of FLO1 phenotype is only inhibited by mannose. It is sensitive to Ca2+ and pH, tolerant to temperature and storage period.