Abeta produced as a fusion to maltose binding protein can be readily purified and stably associates with copper and zinc.
The 42 amino acid Alzheimer's Abeta peptide has been produced in E. coli as a soluble fusion to maltose binding protein (MBP). Affinity purification on amylose columns of MBP-Abeta and MBP led to the recovery of proteins at purities that were suited for physicochemical analyses. MBP-Abeta was able to bind approximately 2 mole equivalents of copper or 4 mole equivalents of zinc, while MBP alone bound negligible amounts of zinc or copper. We conclude that Abeta can bind 2 copper or 4 zinc ions in its fusion format. Because MBP-Abeta is a convenient protein to work with, this system is well suited for further studies on the structure of Abeta and its interactions with metals.
Caine
J
J
CSIRO Molecular and Health Technologies, Parkville, Australia. jo.caine@csiro.au
Volitakis
I
I
Cherny
R
R
Varghese
J
J
Macreadie
I
I
D000595:Amino Acid Sequence; D016229:Amyloid beta-Peptides / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D003300:Copper / Q000378:metabolism*; D004795:Enzyme Stability; D058619:Maltose-Binding Proteins; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D015032:Zinc / Q000378:metabolism*
D016229:Amyloid beta-Peptides; D002352:Carrier Proteins; D058619:Maltose-Binding Proteins; D010446:Peptide Fragments; D011993:Recombinant Fusion Proteins; C075222:amyloid beta-protein (1-42); D003300:Copper; D015032:Zinc