Structure of desheptapeptide (B24-B30) insulin in a new crystal form  

作　　者：包素锦 张季平 常文瑞 梁栋材 

出　　处：《Science China(Life Sciences)》1999年第3期267-273,共7页中国科学（生命科学英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant No. 39270156);the Chinese Academy of Sciences

摘　　要：The structure of desheptapeptide (B24-B30) insulin (DHPI) in a new crystal form (form B) has been determined and refined to 0.2 nm resolution. The crystals were obtained under the same crystallization condition as previously reported crystal form (form A) . The overall structures of the two crystal forms are similar but obvious differences can be observed in crystal packing and local conformation. The crystal structures of the two forms show that the two independent molecules in an asymmetric unit from a DHPI dimer, and the dimer formation buries more than 18.20 and 16.95 nm2 of solvent accessible surfaces for form A and form B DHPI, respectively, the largest among insulin and insulin analogs ever reported. Close examination at crystal packing shows that the dimer-forming surface of DHPI, namely Surface Ⅱ, is normally present in the association of insulin and insulin analogs in their crystal structures. The results demonstrate that Surface II is crucially important for the formation of two crystal forms under the same crystallization condition .The structure of desheptapeptide (B24-B30) insulin (DHPI) in a new crystal form (form B) has been determined and refined to 0.2 nm resolution. The crystals were obtained under the same crystallization condition as previously reported crystal form (form A). The overall structures of the two crystal forms are similar but obvious differences can be observed in crystal packing and local conformation. The crystal structures of the two forms show that the two independent molecules in an asymmetric unit from a DHPI dimer, and the dimer formation buries more than 18.20 and 16.95 nm^2 of solvent accessible surfaces for form A and form B DHPI, respectively, the largest among insulin and insulin analogs ever reported. Close examination at crystal packing shows that the dimer-forming surface of DHPI, namely Surface Ⅱ, is normally present in the association of insulin and insulin analogs in their crystal structures. The results demonstrate that Surface Ⅱ is crucially important for the formation of two crystal

关 键 词：INSULIN desheptapeptide STRUCTURE ASSOCIATION X-RAY crystallography. 

分 类 号：Q57[生物学—生物化学]