日光辐射对大肠杆菌宿主菌和工程菌存活影响的初步研究

PRELIMINARY STUDY ON THE EFFECT OF SOLAR RADIATION ON THE GENETICALLY ENGINEERED AHD HOST ESCHERICHIA COLI

本文观察了不同辐射强度的自然日光照射下，对大肠杆菌宿主菌（Ｋ１２—Ｃ６００）和工程菌（ＭＭ３）在光滑表面（不锈钢）上的存活影响。结果表明，暴露２０ｍｉｎ日光累积总辐射１．１４ＭＪ／ｍ２，宿主菌的存活率为０．０２％，工程菌则为０。散射暴露８０ｍｉｎ，日光累积强度０．９０ＭＪ／ｍ２，宿住菌和工程菌的存活率比值为２：１。黑暗环境下，暴露６天对宿主菌采样仍有细菌存活，工程菌暴露２天的存活率为０。可见，无论是日光总辐射，散射辐射还是黑暗环境，宿主菌的抵抗能力都比工程菌强。在含有４０μｇ／ｍｌ的氟霉素平皿上测定工程菌＊的稳定性，初步测试结果表明，无论是光照还是黑暗环境，该工程菌的质粒都比较稳定。

We observed the effect of solar radiation on the survival of thegenetically engineered Escherichia coli(E,coli K-12 C600,pMM1085)and the host Escherichia coli(E. coli K 12 C600)on the smoothstainless steel surface. The result showed that the survival percentagesof the host E. coli and the engineered E. coli were 0.02% and 0.00%respectively when the direct exposure to solar radiation was extendedto 20 min. (total radiation dosage:1.14MJ/m2),In the diffusioncondition, the ratio of the survival percentage between the hostand the engineered E. coli was 2:1 when exposed for 80 min,In the darkcondition,the engineered E. coli could not be detected on the exposuretime of 2 days,while the host E. coli could survive for 6 days. It isevident that the host E. coli survives better than the engineered E.coli in all the conditions tested,The stability of the geneticallyengineered plasmid was tested on the selective media containingchloromycetin(40 μg/ml),The preliminary study showed that theengineered plasmid was stable in all the conditions tested.