Structure-function analysis of the histidine permease and comparison with cystic fibrosis mutations.
Traffic ATPases constitute a superfamily of transporters that include prokaryotic permeases and medically important eukaryotic proteins, such as the multidrug resistance P-glycoprotein and the cystic fibrosis gene product. We present a structure-function analysis of a member of this superfamily, the prokaryotic histidine permease, using mutations generated both in vitro and in vivo, and assaying several biochemical functions. The analysis supports a previously predicted structural model and allows the assignment of specific functions to several predicted structural features. Mutations in the secondary structure features which form the nucleotide-binding pocket in general cause the loss of ATP binding activity. Mutations in the helical domain retain ATP binding activity. Several mutations have been identified which may affect the signaling mechanism between ATP hydrolysis and membrane translocation. We relate our findings to those emerging from the recent biochemical and genetic analyses of cystic fibrosis mutations.
Shyamala
V
V
Department of Molecular and Cell Biology, University of California, Berkeley 94720.
Baichwal
V
V
Beall
E
E
Ames
G F
GF
D018528:ATP-Binding Cassette Transporters; D000595:Amino Acid Sequence; D026923:Amino Acid Transport Systems, Basic; D001426:Bacterial Proteins; D002478:Cells, Cultured; D003550:Cystic Fibrosis / Q000235:genetics*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D016153:Genes, Suppressor; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D016415:Sequence Alignment; D013329:Structure-Activity Relationship; D013489:Suppression, Genetic
D018528:ATP-Binding Cassette Transporters; D026923:Amino Acid Transport Systems, Basic; D001426:Bacterial Proteins; C505032:CFTR protein, human; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; C043828:histidine permease, Bacteria