| This paper study of six mutagene methods and two kinds of screening methods on Streptomyces spiramyceticus. Among them Co60 rays, UV and LiCl+UV mutagenic effect were good, Chemical mutagenesis influenced stability of S. spiramyceticus; Malonicsodium screening effect was good. U90-5, Col 5-11, Col5-2, P-6 have been selected and biological value were 2576 u/ml,2860 u/ml, 2714u/ml,2907u/ml. All Mutations increased above 15%.The titer increase of Co15-11 rock culture was 26.05% compared to primitive strain CK25-1,and in the 15L pot fermentation was 14.4%. Carbon metabolism current distribution:When 18h, the Mutate strain glucose consumption and EMP carbon proportion were lower, HMS was higher, TCA both almost; When 48h, the former sugar consumption and HMS both were higher, EMP was still lower, TCA both reduced. From 18h to 48h, EMP and TCA both reduced, but HMS increased significantly. In product synthesis time, reduced energy, increased HMS flux, could be advantageous to SPM production.Pantothenic acid calcium, thioctic acid, biotin andVB12 all could promote SPM production. The order of significance was:thioctic acid>VB12> biotin> Pantothenic acid calcium. The best combination was:Pantothenic acid calcium 0.005mg/L, thioctic acid 0.4 mg/L, biotin 0.188 mg/L,VB120.04 mg/L.The optimum feeding time was 12h and value was increased by 16.9%.Adding of 2% KNO3 at 24h in fermentation had the best effect on SPM. Rocker potency enhanced 17.7% and pot enhanced 10.66%. KNO3 could enhance unit mycelium using Sugar, intraccllular ATP reduced, expanded TCA early flux and promoted succinic acid transform to methyl malonyl COA, increased AS activity.Adding acetamide enhanced 14.3% of SPM potency, the best time and concentration were 28h-32h and 0.1%. The change of SPM three components in the process by HPLC, Within 85h, acetamide caused SPMⅠinto SPMⅡ,Ⅲ, advised it could promote C3 acylation enzyme activity and provide 2C precursor for SPM synthesis. |
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