Studies On Establishment And Biological Characteristic Of Fusants Of BS-1 And SM-1

BS-1 with high amylase and phytase activity and SM-1 which could decompose cellulose effectively were tried to integrate into a fusant by protoplast fusion.In the end ,a multifunctional engineering-strain which had the amylase,phytase,and cellulase activity was constructed. Speciticmeasures and research results were showed as follows:1. A bacrterium named BS-1 was screened from aquatic feed. It was proved to secretes large amount of amylase and phytase.2. We measured the growth curve of BS-1 and SM-1 by means of spectrophotometer respectively . The results showed that the logarithmic metaphase of growth of the two strans were 6 hours and 6.5 hours respectively.3. Discussing factors which affect the formation rate and regeneration rate of BS-1 and SM-1 by means of one-way experiment. The results showed that: The best enzyme treating solution of the BS-1 was 5mg/ml, but the SM-1 was 6mg/ml; the best treating time was 60min .At this enzyme treating solution and time, the percentages of protoplast formation and protoplast regeneration of the BS-1 were 90.28% and 10.80%respectively. But the SM-1 were 78.66% and 9.70%.4. Choosing the heat-treating protoplast to destroy the protoplast of SM-1. The results showed that: the best treating temperature was 60 ℃ and treating time was 50min.5. At 37℃ in water bath, the protoplasts of the two strains were be fusing 60min at PEG6000 andCa²⁺, and the geneticly stable fusants were screened. 87 fusants were isolated on selecting culture medium and make them exist from the fist generation to the 10th generation,getting a geneticly stable fusants fusants .6. Comparing the appearance of colony, micrososmic configuration, physiological and bio-chemiccharacter experiment of the parent and fusant to identity the fusant preliminarily.7. Identifying the fusant further by means of DNA electrophoresis to get the...