Premium
Cloning and characterization of a LON gene homologue from the human pathogen Paracoccidioides brasiliensis
Author(s) -
Barros Tânia F.,
Puccia Rosana
Publication year - 2001
Publication title -
yeast
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.923
H-Index - 102
eISSN - 1097-0061
pISSN - 0749-503X
DOI - 10.1002/yea.745
Subject(s) - biology , paracoccidioides brasiliensis , gene , genetics , heat shock protein , chaperone (clinical) , microbiology and biotechnology , medicine , pathology
A LON gene homologue from the human pathogen Paracoccidioides brasiliensis ( PbLON ) has been cloned, sequenced and characterized. It encodes a putative ATP‐dependent proteinase Lon, which in Saccharomyces cerevisisae (PIM1) is a heat‐inducible protein involved in the degradation of abnormal or short‐lived proteins in the mitochondria. The PbLON ORF is within a 3369 bp fragment interrupted by two introns located in the 3′segment. The 5′ and 3′ regions flanking the ORF contain sequences which resemble known transcription elements. Several transcription binding factor motifs have also been found, including sites for heat shock/stress response and nitrogen control. The deduced protein consists of 1063 residues containing a mitochondrial import signal at the N‐terminus and conserved ATP‐binding (GPPGVGKT) and serine catalytic (KDGPSAG) sites. It shares high identity with Lon homologues from S. cerevisiae (73%), Homo sapiens (62%) and Escherichia coli (56%). In P. brasiliensis , an MDJ1 putative gene has also been partially sequenced adjacent to PbLON , possibly sharing divergently orientated promoter elements. This chromosomal organization is interesting, since Mdj1p is a heat shock chaperone essential for substrate degradation by PIM1 in yeast. The LON nucleotide andflanking sequence regions have been submitted to GenBank under Accession No. AF239178. Copyright © 2001 John Wiley & Sons, Ltd.