意大利 OLMA 公司自动钣金生产线,经过长时间使用后,各方面的毛病随之而来。设备废品率一度曾达到30%,设备定位经常被挤坏,铜瓦、丝杠、齿轮易磨损等等,严重制约了生产的正常进行。为了能更好地保证生产,借鉴其它设备的优点,对其进行优...意大利 OLMA 公司自动钣金生产线,经过长时间使用后,各方面的毛病随之而来。设备废品率一度曾达到30%,设备定位经常被挤坏,铜瓦、丝杠、齿轮易磨损等等,严重制约了生产的正常进行。为了能更好地保证生产,借鉴其它设备的优点,对其进行优化改造。对设备改造的同时,充分了解到该设备机械、液压系统、润滑系统、位移检测系统以及机械的磨损情况以及液压单向阀、磁伴开关的工作原理及使用方法。展开更多
Gene deletion vector pXL05(pKC1139∷△olmA1 +△olmA4) was used to disrupt oligomycin PKS en-coding genes (olmA) in Streptomyces avermitilis CZ8-73, the producer of anthelmintic avermectins B and the cell growth inhibi...Gene deletion vector pXL05(pKC1139∷△olmA1 +△olmA4) was used to disrupt oligomycin PKS en-coding genes (olmA) in Streptomyces avermitilis CZ8-73, the producer of anthelmintic avermectins B and the cell growth inhibitor oligomycin. olmA gene cluster in the chromosome was displaced by deletion allele on the plasmid via double crossover. Four of disruptants were confirmed by Southern blotting. Shaking flask experiments and HPLC analyses showed that the four mutants no longer produced the toxic oligomycin, but only made four components of avermectins B, which were avermectin B1a, B1b, B2a, B2b. The yields of avermectins B in these mutants were separately equal to those in CZ8-73. This revealed that olmA genes deletion did not affect the biosynthesis of avermectins. The deletion mu-tants were proved to be genetically stable, and thus might be promising strains in industrial production of avermectins B.展开更多
文摘意大利 OLMA 公司自动钣金生产线,经过长时间使用后,各方面的毛病随之而来。设备废品率一度曾达到30%,设备定位经常被挤坏,铜瓦、丝杠、齿轮易磨损等等,严重制约了生产的正常进行。为了能更好地保证生产,借鉴其它设备的优点,对其进行优化改造。对设备改造的同时,充分了解到该设备机械、液压系统、润滑系统、位移检测系统以及机械的磨损情况以及液压单向阀、磁伴开关的工作原理及使用方法。
文摘Gene deletion vector pXL05(pKC1139∷△olmA1 +△olmA4) was used to disrupt oligomycin PKS en-coding genes (olmA) in Streptomyces avermitilis CZ8-73, the producer of anthelmintic avermectins B and the cell growth inhibitor oligomycin. olmA gene cluster in the chromosome was displaced by deletion allele on the plasmid via double crossover. Four of disruptants were confirmed by Southern blotting. Shaking flask experiments and HPLC analyses showed that the four mutants no longer produced the toxic oligomycin, but only made four components of avermectins B, which were avermectin B1a, B1b, B2a, B2b. The yields of avermectins B in these mutants were separately equal to those in CZ8-73. This revealed that olmA genes deletion did not affect the biosynthesis of avermectins. The deletion mu-tants were proved to be genetically stable, and thus might be promising strains in industrial production of avermectins B.
