Distribution and molecular epidemiologic characterizes of insertion sequence IS1301 in neisseria meningitidis isolated from China

Abstract

To research the distribution and molecular epidemiology of insertion sequence IS1301 in Neisseria (N.) meningitidis strains in China, so as to provide scientific and available evidence for a new method of genotyping in N. meningitidis strains with IS1301. Examined the IS1301 by PCR in 219 N.meningitidis strains from 16 provinces and 3 cities during 2007 and 2008 in China, productions of amplification were sent for sequencing. The positive N. meningitidis strains were analyzed by pulse field gel electrophoresis (PFGE) and nucleic acid blotting hybridization(Southern blot) by electrophoresis. The positive rates with IS1301 were 15.53%, 11.11%, 20.75%,6.17% and 28.57% for four serotypes (A, B, C, N) respectively. The sequence comparability between the amplification productions and No.Z49092.1 N. meningitidis which registered in GenBank was 94%-100%. There were two types of clusters divided by cladogram analysis. There appeared large IS1301 sequence difference between the serotype C and others. The number of IS1301 replica ranged from 6-17 per strain at least. The number of IS1301 replica changed in the same type of PFGE N. meningitidis respectively. Typing by IS1301 combined with PFGE could comprehend the homology and genetic polymorphism of N.meningitidis epidemic strains at the molecular level.