Premium
A Cys‐less variant of the bacterial ATP binding cassette protein MalK is functional in maltose transport and regulation
Author(s) -
Hunke Sabine,
Schneider Erwin
Publication year - 1999
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(99)00356-7
Subject(s) - maltose , maltose binding protein , atp binding cassette transporter , biochemistry , chemistry , enzyme , gene , transporter , recombinant dna , fusion protein
The cysteine residues of the ABC protein MalK from Salmonella typhimurium maltose transport system (C40, C350, C360) were consecutively replaced by serines. Cys‐less MalK was fully functional in maltose transport in vivo. Moreover, the activity of MalK as a repressor of other maltose‐regulated genes was also retained. The absence of cysteine residues in the purified protein was verified by its failure to react with fluorescein‐5‐maleimide. In contrast to purified wild‐type MalK, the ATPase activity of the C40S variant was insensitive to inhibition by N ‐ethylmaleimide.