| Nitrile Hydratase is an enzyme which can catalyse acrylonitrile to acrylamide. The generation of Nitrile Hydratase was the crucial step in producing acrylamide using biotransformation method, it affected the yield, the quality and the economic benefit of acrylamide directly. Acrylamide is a precise organic chemical industry material which produces polyacrylamide. Polyacrylamide is used as oil development, water treatment, paper manufacture, printing and dyeing, coal et al, and have a wide application in foods, sugar manufacturing, medicine.With the growing demand for acrylamide, Chinese and foreign scholars have a widely research in Nitrile Hydratase producing strain. They did many studies in microbial strain selection, form condition of enzyme and fermentation course optimization control, so have borne fruit. In recent years, they make an intensive study of enzyme structure and property, and disclose the catalytic mechanism of Nitrile Hydratase to molecule level. These studies have significance in improving enzymatic activity and stabilizing enzyme. Strain-improving is the core technology of strain improvement, the general mutation breeding is to treat microorganism with UV., radiation or chemical mutagen, then filter strain. Forward mutation rate is very low, ordinarily 10-4. The train evolved out of a long process of mutation, so its specific characters were improved, simultaneity accumulating detrimental mutations which extraned to specific characters, for example: growth conditions turned rigor, viability was weak, the cell turned brittleness, et al. Crossbreeding used donor and receptor which characters were given as parents, so it advanced much more than mutation breeding whether in directivity or consciousness. Since crossbreeding is very complex, it is more difficult than mutation breeding to spread and use, especially in the field of prokaryote, it is rary to breed high-yield strain by using genome shuffling. Molecular breeding inherited and improved crossbreeding, it accelerated the breeding-schedule by using new notion and method, so its foreground is abroad, it used in gene, metabolic pathway even in whole genome breeding. The object of genome shuffling is the whole cell, it made cross breeding to mutation strain, and cause different strain's genome to recombine completely, the chance of various forward mutation concordance to a recon improved. Simultaneity, accumulative detrimental mutation was replaced by the sequence of wild type strain. Hence, improved recon was detected by high flux,then entered the next genome shuffling, the forward mutation rate can be enhanced greatly. So, using Nocardia sp. as original strain, which produces Nitrile Hydratase, this research subject used antibiotic-resistance as sign, then prepared proplasts and made microwave mutagism and fusion to them. Then we selected a strain with the higher enzymatic activity by genome shuffling. Consequently, we raised efficient production of acrylamide. Finally, we studied the physiology property and fermentation course optimization control of the mutation strain. As a result, we improved the enzyme-producing of the strain and their adaptability. The results included the following several aspects: 1. Screen out of antibiotic-resistance strains by genome shuffling. Then, the enzymatic activities of the two strains which were obtained were54670 ug/ml.hr and 53960 ug/ml.hr respectly. After several generations culture, the fermentation tests showed that enzyme activity is improved 36.4%, fermentation period is 20hr shorter in fermentation tank, conditions of culture were no changed evidencely, so it suits for the existing process conditions, we can use it in industrial production. 2. Protoplast preparation and regeneration: conditions about protoplast optimization preparation of Nocardia sp., which could produce Nitrile Hydratase, were studied by orthogonal experiments, including the concentration of preculture and lysozyme, lytic time, hypha culture time,etc . As a result, hypha culture time 36hr, Gly 0.2%, lysozyme 2mg/ml, lytic time 40...
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