TY - JOUR
T1 - Identification and sequencing of the groE operon and flanking genes of Lawsonia intracellularis
T2 - Use in phylogeny
AU - Dale, C. Jane H.
AU - Moses, Eric K.
AU - Ong, Chin Chui
AU - Morrow, Chris J.
AU - Reed, Michael B.
AU - Hasse, Dete
AU - Strugnell, Richard A.
PY - 1998/8
Y1 - 1998/8
N2 - Proliferative enteropathy (PE) is a complex of diseases of commercial importance to the pig industry. The obligate intracellular bacterium Lawsonia infracellularis is consistently associated with PE and pure cultures of this bacterium have been used to reproduce PE in pigs. In this study L. intracellularis bacteria were purified directly from PE-affected tissue. DNA extracted from purified bacteria was used to construct a partial genomic library which was screened using sera from L. intracellularis-immunized rabbits. Two seroreactive recombinant clones were identified, one of which expressed proteins of 10 and 60 kDa. The sequence of the insert from this clone, pISI-2, revealed ORFs with sequence similarity to the groES/EL operon of Escherichia coli, the 50S ribosomal proteins L21 and L27 of E. coli, a GTP-binding protein of Bacillus subtilis and a possible protoporphyrinogen oxidase, HemK, of E. coli. Primers designed from unique sequences from the pISI-2 insert amplified DNA from infected, but not non-infected, porcine ilea; the amplicon sequence obtained from tissue-cultured L. intracellularis was identical to the corresponding sequence in pISI-2, confirming the origin of the clone. The sequence of L. intracellularis GroEL and other GroEL sequences in the databases were used to construct a partial phylogenetic tree. Analysis of the GroEL sequence relationship suggested that L. intracellularis is not significantly related to other organisms whose GroEL sequences are held in the databases and supports previous data from 16S sequence analyses suggesting that L. intracellularis is a member of a novel group of enteric pathogens.
AB - Proliferative enteropathy (PE) is a complex of diseases of commercial importance to the pig industry. The obligate intracellular bacterium Lawsonia infracellularis is consistently associated with PE and pure cultures of this bacterium have been used to reproduce PE in pigs. In this study L. intracellularis bacteria were purified directly from PE-affected tissue. DNA extracted from purified bacteria was used to construct a partial genomic library which was screened using sera from L. intracellularis-immunized rabbits. Two seroreactive recombinant clones were identified, one of which expressed proteins of 10 and 60 kDa. The sequence of the insert from this clone, pISI-2, revealed ORFs with sequence similarity to the groES/EL operon of Escherichia coli, the 50S ribosomal proteins L21 and L27 of E. coli, a GTP-binding protein of Bacillus subtilis and a possible protoporphyrinogen oxidase, HemK, of E. coli. Primers designed from unique sequences from the pISI-2 insert amplified DNA from infected, but not non-infected, porcine ilea; the amplicon sequence obtained from tissue-cultured L. intracellularis was identical to the corresponding sequence in pISI-2, confirming the origin of the clone. The sequence of L. intracellularis GroEL and other GroEL sequences in the databases were used to construct a partial phylogenetic tree. Analysis of the GroEL sequence relationship suggested that L. intracellularis is not significantly related to other organisms whose GroEL sequences are held in the databases and supports previous data from 16S sequence analyses suggesting that L. intracellularis is a member of a novel group of enteric pathogens.
KW - Heat-shock protein
KW - Lawsonia intracellularis
KW - Proliferative enteropathy
KW - groE operon
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U2 - 10.1099/00221287-144-8-2073
DO - 10.1099/00221287-144-8-2073
M3 - Article
C2 - 9720028
AN - SCOPUS:0031719292
VL - 144
SP - 2073
EP - 2084
JO - Journal of General Microbiology
JF - Journal of General Microbiology
SN - 1350-0872
IS - 8
ER -