用 X 射线单晶结构分析测定了天花粉母液中两个组分的结构,晶体结构由直接法解出.二水合 L-瓜氨酸属正交空间群 D-P222;a=4.671(4),6=13.07(1),c=16.40(1)(?);V=1001(1)(?);Z=4.由898个反射点参与修正,R=0.057.α-羟甲基丝氨酸属三斜空...用 X 射线单晶结构分析测定了天花粉母液中两个组分的结构,晶体结构由直接法解出.二水合 L-瓜氨酸属正交空间群 D-P222;a=4.671(4),6=13.07(1),c=16.40(1)(?);V=1001(1)(?);Z=4.由898个反射点参与修正,R=0.057.α-羟甲基丝氨酸属三斜空间群 C-PI;a=7.935(1),b=7.935(1),c=19.029(2)(?);α=98.81(1),β=98.97(1),γ=90.10(1)°;V=1169.1(3)(?);Z=8.由3394个衍射点参与修正,R=0.054.对用 X 射线单晶结构分析测定未知天然产物的结构进行了讨论.展开更多
Protein crystal growth is quite important for the determination of protein structureswhich are essential to the understanding of life at molecular level as well as to the development of molecu-lar biotechnology.The mi...Protein crystal growth is quite important for the determination of protein structureswhich are essential to the understanding of life at molecular level as well as to the development of molecu-lar biotechnology.The microgravity environment of space is an ideal place to study the complicated pro-tein crystallization and to grow good-quality protein crystals.A number of crystal-growth experiments of10 different proteins were carried out in August,1992 on the Chinese re-entry satellite FSW-2 in spaceusing a tube crystallization equipment made in China.A total of 25 samples from 6 proteins producedcrystals,and the effects of microgravity on protein crystal growth were observed,especially for an acidicphospholipase A2 and henegg-white lysozyme which gave better crystals in space than earth-grown crys-tals in ground control experiments.The results have shown that the microgravity in space favors the im-provement of the size,perfection,morphology and internal order of the grown protein crytals.展开更多
The cross\|linked crystals of Concanavalin A were soaked in water and in anhydrous acetonitrile as well as were re\|soaked in water after soaking in acetonitrile. Their structures were determined by X\|ray crystallogr...The cross\|linked crystals of Concanavalin A were soaked in water and in anhydrous acetonitrile as well as were re\|soaked in water after soaking in acetonitrile. Their structures were determined by X\|ray crystallography and compared with the uncross\|linked native structure. One of them, which was soaked in net acetonitrile, underwent considerable changes in the diffraction pattern when soaked in net acetonitrile. Its cell parameters are 0.45 and 0.57 nm shorter in a axis and in b axis, but 0.12 nm longer in c axis than those of the native, respectively. It was found that acetonitrile has an effect on the conformation of poly peptide chain in the flexible turn and loop regions, except for β sheets. The confomation of cross\|linked structure in soaked acetonitrile may recorvered to the native when re\|soaked in water, and its conserved acetonitrile molecule is used as a probe to exploit the regions of protein surface with specificity and affinity.展开更多
文摘用 X 射线单晶结构分析测定了天花粉母液中两个组分的结构,晶体结构由直接法解出.二水合 L-瓜氨酸属正交空间群 D-P222;a=4.671(4),6=13.07(1),c=16.40(1)(?);V=1001(1)(?);Z=4.由898个反射点参与修正,R=0.057.α-羟甲基丝氨酸属三斜空间群 C-PI;a=7.935(1),b=7.935(1),c=19.029(2)(?);α=98.81(1),β=98.97(1),γ=90.10(1)°;V=1169.1(3)(?);Z=8.由3394个衍射点参与修正,R=0.054.对用 X 射线单晶结构分析测定未知天然产物的结构进行了讨论.
文摘Protein crystal growth is quite important for the determination of protein structureswhich are essential to the understanding of life at molecular level as well as to the development of molecu-lar biotechnology.The microgravity environment of space is an ideal place to study the complicated pro-tein crystallization and to grow good-quality protein crystals.A number of crystal-growth experiments of10 different proteins were carried out in August,1992 on the Chinese re-entry satellite FSW-2 in spaceusing a tube crystallization equipment made in China.A total of 25 samples from 6 proteins producedcrystals,and the effects of microgravity on protein crystal growth were observed,especially for an acidicphospholipase A2 and henegg-white lysozyme which gave better crystals in space than earth-grown crys-tals in ground control experiments.The results have shown that the microgravity in space favors the im-provement of the size,perfection,morphology and internal order of the grown protein crytals.
文摘The cross\|linked crystals of Concanavalin A were soaked in water and in anhydrous acetonitrile as well as were re\|soaked in water after soaking in acetonitrile. Their structures were determined by X\|ray crystallography and compared with the uncross\|linked native structure. One of them, which was soaked in net acetonitrile, underwent considerable changes in the diffraction pattern when soaked in net acetonitrile. Its cell parameters are 0.45 and 0.57 nm shorter in a axis and in b axis, but 0.12 nm longer in c axis than those of the native, respectively. It was found that acetonitrile has an effect on the conformation of poly peptide chain in the flexible turn and loop regions, except for β sheets. The confomation of cross\|linked structure in soaked acetonitrile may recorvered to the native when re\|soaked in water, and its conserved acetonitrile molecule is used as a probe to exploit the regions of protein surface with specificity and affinity.
