An aliquot (150 g) of the pooled final fractions was fractionated by SDS/PAGE (10%), and, after transfer to nitrocellulose, the major band at 130 kDa, which was positive in the filter-overlay assay, was excised for proteolytic fragmentation and peptide microsequencing … Continue reading An aliquot (150 g) of the pooled final fractions was fractionated by SDS/PAGE (10%), and, after transfer to nitrocellulose, the major band at 130 kDa, which was positive in the filter-overlay assay, was excised for proteolytic fragmentation and peptide microsequencing (22, 23)