Location of the intermediate and high affinity omega-aminocarboxylic acid-binding sites in human plasminogen.

Abstract

T w o elastase fragments of plasminogen, Tyr7e-Valss7/ Tyr7,,-VabS3 and Va13s4-Ala43e (kringle 1 + 2 + 3 and kringle 4), are known to bind to lysine-Sepharose.Elastase fragmentation of Glu-and Lys-plasminogen that lost affinity for lysine-Sepharose as a result of 1,242~clohexanedione modification yields kringle 1 + 2 + 3 that no longer displays affinity for lysine-Sepharose; the kringle 4 fragment, however, is bound normally to the affinity column.These results show that the binding site of kringle 4 is not functional in plasminogen and it ' The abbreviations used are: r-Ahx, e-aminohexanoic acid; Glu-Pg, native plasminogen, Glu,-Asn~~; Lys-Pg, proteolytically modified plasminogen, Lys78-Asn7w; kringle 1 + 2 + 3, plasminogen fragment, Tyr79-Valas7 and Tyr79-Vala53; kringle 4, plasminogen fragment, V a h -Alaag; miniplasminogen, plasminogen fragment, VaL4~-Asn7~; cHxO2.1,2-cyclohexanedione; DodSOI, sodium dodecyl sulfate.