Carboxypeptidase that catalyzes the release of a C-terminal amino acid, but has little or no action with -Asp, -Glu, -Arg, -Lys or -Pro (PubMed:20385563, PubMed:8806703). Catalyzes the conversion of leukotriene C4 to leukotriene F4 via the hydrolysis of an amide bond (By similarity). {ECO:0000250|UniProtKB:P00730, ECO:0000269|PubMed:20385563, ECO:0000269|PubMed:8806703}. This is the function of CPA1 (carboxypeptidase A1, Ensembl gene identifier ENSG00000091704).