Chain A ( N38 K39 M40 F41 C42 Q43 L44 K71 V80 L101 Y141 N142 Y143 M144 C145 N146 S147 S148 C149 M153 R155 R156 P157 I158 E178 V179 R180 V181 C182 A183 C184 D188 T191 E192 )