passages.id: split_5_test_2651_passage
passages.type: progene_text
passages.text: Only the gamma 2 alpha 1 beta 3 alpha 1 beta 3 arrangement satisfied three known criteria : (1) alpha 1 His ( 102 ) binds at the gamma 2 subunit interface in proximity to gamma 2 residues Thr ( 142 ) , Phe ( 77 ) , and Met ( 130 ) ; ( 2 ) alpha 1 residues 80 - 100 bind near gamma 2 residues 91 - 104 ; and (3) alpha 1 residues 58 - 67 bind near the beta 3 subunit interface .