Chain A ( G95 V96 L98 A99 L100 V101 L102 N103 L104 L105 Q106 I107 R109 I122 W128 V129 C132 C133 G134 T135 A136 A137 A138 V139 V140 G141 L143 Y144 F171 V172 N175 H176 S178 A179 G210 G212 L213 G214 I215 T216 I217 A218 F219 L220 A221 T222 L223 I224 T225 L228 Y234 Y236 I244 R245 W247 L248 P249 C250 I251 F252 F253 S254 G255 G256 V257 V259 )