Transcription in Mycoplasma pneumoniae: analysis of the promoters of the ackA and ldh genes.
The nucleotide sequences that control transcription initiation and regulation in Mycoplasma pneumoniae are poorly understood. Moreover, only few regulatory events have been reported for M. pneumoniae. We have studied changes in the global protein synthesis pattern in M. pneumoniae in response to the presence of glycerol. The ackA and ldh genes, encoding acetate kinase and lactate dehydrogenase, respectively, were controlled in a carbon source-dependent manner. While the ackA gene was strongly expressed in the presence of glucose, transcription of ldh was induced by glycerol. The promoters of both genes were mapped by primer extension analysis. Molecular analysis of transcription regulatory mechanisms in M. pneumoniae has so far not been possible due to the lack of appropriate reporter systems that can be used to study the activity of promoter fragments and their mutant derivatives in vivo. Recently, a reporter system has been developed which allows cloning of promoter fragments in front of a promoterless lacZ gene and inserting this construct into the genome of M. pneumoniae. To study the requirements of M. pneumoniae RNA polymerase for promoter recognition, a series of fusions of deletion and mutant variants of the ldh promoter was constructed and analyzed in vivo. While mutations affecting the -10 region strongly interfered with gene expression, the -35 region seems to be of minor importance in M. pneumoniae.
Halbedel
Sven
S
Department of General Microbiology, Institute of Microbiology and Genetics, Georg-August University Göttingen, Germany.
Eilers
Hinnerk
H
Jonas
Beate
B
Busse
Julia
J
Hecker
Michael
M
Engelmann
Susanne
S
Stülke
Jörg
J
D000084:Acetate Kinase / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D004252:DNA Mutational Analysis; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D005798:Genes, Bacterial; D005947:Glucose / Q000494:pharmacology; D005990:Glycerol / Q000494:pharmacology; D007770:L-Lactate Dehydrogenase / Q000235:genetics*; D009177:Mycoplasma pneumoniae / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development; D011401:Promoter Regions, Genetic / Q000235:genetics*; D020543:Proteome / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion; D014158:Transcription, Genetic / Q000187:drug effects
D001426:Bacterial Proteins; D020543:Proteome; D012333:RNA, Messenger; D007770:L-Lactate Dehydrogenase; D000084:Acetate Kinase; D005947:Glucose; D005990:Glycerol