Cloning and characterization of the genes encoding a glycine betaine ABC-type transporter in Halobacillus trueperi DSM10404T.
By using Southern blot hybridization and inverse polymerase chain reaction, a 5.5-kb DNA fragment was obtained from the genomic DNA of Halobacillus trueperi DSM10404(T). Sequence analysis revealed that it contained a potential operon with high levels of sequence similarity to the opuA operon encoding glycine betaine transporter from Bacillus subtilis, which is a member of the ATP-binding cassette (ABC) substrate binding the protein-dependent transporter superfamily. The potential operon, designated as qatA (quaternary amine transporter), consists of three structural genes, which are predicted to encode an ATP-binding protein (QatAA), a membrane-associated protein (QatAB), and an extracellular substrate-binding protein (QatAC). Moreover, the putative promoter region of the operon was found with close homology to the sigma(A)-dependent promoter of B. subtilis. Reverse transcription (RT)-PCR analysis revealed that qatAA, qatAB, and qatAC genes were transcribed in cells of H. trueperi. Cells of Escherichia coli mutant MKH13 harboring qatA on pAY41 were able to grow on selective M9 salt medium containing glycine betaine and accumulated glycine betaine in the cytoplasm, showing that qatAA, qatAB, and qatAC genes together encode a functional glycine betaine transporter.
Lu
Weidong
W
Department of Microbiology, College of Biological Sciences, China Agricultural University, Key Laboratory of Agro-Microbial Resources and Application, Ministry of Agriculture, Beijing, People's Republic of China.
Zhang
Bo
B
Zhao
Baisuo
B
Feng
Deqin
D
Yang
Lifu
L
Wang
Lei
L
Yang
Susheng
S
D018528:ATP-Binding Cassette Transporters / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D000595:Amino Acid Sequence; D001406:Bacillaceae / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001622:Betaine / Q000378:metabolism*; D003001:Cloning, Molecular; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
D018528:ATP-Binding Cassette Transporters; D001426:Bacterial Proteins; D001622:Betaine