Premium
Comparative characterization of the iga gene encoding IgA1 protease in Neisseria meningitidis, Neisseria gonorrhoeae and Haemophilus influenzae
Author(s) -
Lomholt Hans,
Poulsen Knud,
Kilian Mogens
Publication year - 1995
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1111/j.1365-2958.1995.tb02263.x
Subject(s) - neisseria meningitidis , biology , neisseria gonorrhoeae , haemophilus influenzae , neisseria , microbiology and biotechnology , neisseriaceae , gene , virology , genetics , bacteria , antibiotics
Summary Cloning and sequencing of the IgA1 protease gene ( iga ) from Neisseria meningitidis strain HF13 showed an overall structure equivalent to iga genes from Neisseria gonorrhoeae and Haemophilus influenzae , although no region corresponding to the gonococcal α‐peptide was evident. An additional 18 N. meningitidis and 3 H. influenzae iga genes were amplified by the polymerase chain reaction technique and sequenced corresponding approximately to the N ‐terminal half of the mature enzyme. Comparative analyses of a total of 29 iga genes showed that pathogenic Neisseria have iga genes with a significantly lower degree of heterogeneity than H. influenzae iga genes. Recombinational events indicated by mosaic‐like structures corresponding to those found among N. gonorrhoeae protease genes were detected among N. meningitidis iga genes. One region showed characteristic differences in sequence and length which correlated with each of the different cleavage specificities. Meningococci were extremely conserved in this region with no evidence of recombination between isolates of different cleavage specificities. Sequences further downstream showed no obvious relationship with enzyme cleavage type. This region consisted of conserved areas interspersed with highly variable areas. Amino acid sequence homologies in the variable regions of meningococci reflected the antigenic types defined by using polyclonal neutralizing antibodies.