氯灭活甲型肝炎病毒与其核酸变化关系的研究

STUDY ON RELATIONSHIP BETWEEN CHLORINE INACTIVATION OF HEPATITIS A VIRUS AND CHANGES IN NUCLEIC ACID OF HAV

为了解氯灭活ＨＡＶ与ＨＡＶ核酸变化的关系，采用大片段逐步步移ＲＴ一ＰＣＲ技术对ＨＡＶ核酸全序列进行扫描。结果，在２５℃以１０ｍｇ／Ｌ有效氯作用３０ｍｉｎ，可完全灭活ＨＡＶ，而５ｍｇ／Ｌ有效氯作用６０ｍｉｎ则不能。在ＨＡＶ核酸全序列中，各部分对氯的抗力不一，以５′ＮＴＲ为敏感。用１０ｍｇ／Ｌ有效氯作用３０ｍｉｎ，检测其为阴性，其次为３′ＮＴＲ，当１０ｍｇ／Ｌ有效氯作用６０ ｍｉｎ时，亦为阴性；结构区的某些片段对氯的抗力较强。以１０ｍｇ／Ｌ有效氯作用３０ｍｉｎ，进一步缩小氯对ＨＡＶ核酸作用敏感区间｛即近５′ＮＴＲ）的检测发现，病毒最初的１～６７１ｂｐ检测呈阴性，而６６９～１０２３ｂｐ仍呈阳性。结果表明，氯灭活ＨＡＶ与其核酸５′ＮＴＲ的损伤一致，在充分了解氯对ＨＡＶ作用机理的基础上，ＰＣＲ可用于消毒效果的评价。

In order to know the relationship between chlorine inactivation of HAV and the changes in nucleic acid of HAV. The entire sequence of HAV nucleic acid was scanned using long-overlapping RT-PCR technique. The results showed that available chlorine 10 mg/ L with a 30 minute contact time at 25℃ could completely inactivate HAV, while available chlo- rine 5mg/L with a 60 minute contact time could not. Different parts of the entire sequence of HAV nucleic acid had different resistance to chlorine. 5′NTR was the most sensitive one and became negative on examination after exposure to available chlorine 10 mg/L for 30 minutes. The next sensitive one was 5′ NTR which also became negative on examination after exposure to available chlorine 10 mg / L for 60 min. Some fragments of the structural domain had strong resistance to chlorine. After exposure to available chlorine 10 mg/ L for 30 min, examination of reduced domain of HAV nucleic acid (in the vicinity of 5′ NTR) sensitive to chlorine found that the first 1-671 bp of the virus was negative on examination, while 669- 1023 bp was still positive. The study indicated that chlorine inactivation of HAV conformed to the damage of 5′ NTR of its nucleic acid. On the besis of full knowledge of the mechanism of effect of chlorine on HAV, PCR can be used for evaluation of disinfection efficacy.