passages.id: split_6_test_561_passage
passages.type: progene_text
passages.text: When a recombinant protein , consisting of protein A fused to the COOH - terminal luminal domain of the human mannosidase homolog , was expressed in COS cells , the fusion protein was found to cleave only a single alpha1,2-mannose residue from Man(9)GlcNAc(2) to produce a unique Man ( 8 ) GlcNAc(2) isomer ( Man8B ) .