Lahiri S S, Karothia B S
Defence Research & Development Establishment, Gwalior.
Indian J Med Res. 1994 Jan;99:18-20.
Twenty four Esch. coli isolates obtained from patients of diarrhoea were tested by DNA hybridization for presence of enterotoxigenic Esch. coli (ETEC). The probe generated for this study was labelled by two different ways using the large Klenow fragment of DNA polymerase-I. It was observed that labelling by sequential harnessing of the exonuclease and polymerase activity of the enzyme was superior to extension of random hexanucleotide primers. This method besides being economic, dispenses with the critical step involved in the thermodynamics of oligoannealing and initiation of DNA synthesis.
对从腹泻患者中分离出的24株大肠杆菌进行DNA杂交检测，以确定是否存在产肠毒素大肠杆菌（ETEC）。本研究中制备的探针采用DNA聚合酶I的大片段Klenow片段通过两种不同方法进行标记。结果发现，通过依次利用该酶的核酸外切酶和聚合酶活性进行标记，优于随机六核苷酸引物延伸法。该方法除了经济之外，还省去了寡核苷酸退火热力学和DNA合成起始过程中涉及的关键步骤。
