Lipoamide dehydrogenase of Staphylococcus aureus: nucleotide sequence and sequence analysis

Area of Science:

• Microbiology
• Molecular Biology
• Biochemistry

Background:

• A previously isolated protein complex from Staphylococcus aureus interacted strongly with membrane-bound ribosomes.
• This interaction suggested a role in protein secretion, but the complex was identified as pyruvate dehydrogenase (PDH).
• The identification of PDH disproved its direct involvement in protein secretion.

Purpose of the Study:

• To report the nucleotide sequence of the pdhD gene from the S. aureus pyruvate dehydrogenase operon.
• To characterize the encoded lipoamide dehydrogenase (LPD) protein.

Main Methods:

• Nucleotide sequencing of the pdhD gene.
• Bioinformatic analysis of the deduced protein sequence.

Main Results:

• The nucleotide sequence of the final gene, pdhD, in the S. aureus pyruvate dehydrogenase operon was determined.
• The pdhD gene encodes lipoamide dehydrogenase (LPD), a protein of 468 amino acids with a molecular mass of 49.5 kDa.
• The deduced LPD protein shows close homology to other bacterial and eukaryotic lipoamide dehydrogenases.

Conclusions:

• The characterization of pdhD provides a complete understanding of the S. aureus pyruvate dehydrogenase operon.
• The study discusses the potential role of membrane-bound lipoamide dehydrogenase in S. aureus.