Schulze-Gahmen Ursula, Aono Shelly, Chen Shengfeng, Yokota Hisao, Kim Rosalind, Kim Sung Hou
Berkeley Structural Genomics Center, Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Acta Crystallogr D Biol Crystallogr. 2005 Oct;61(Pt 10):1343-7. doi: 10.1107/S090744490502264X. Epub 2005 Sep 28.
The crystal structure of the hypothetical protein MPN555 from Mycoplasma pneumoniae (gi|1673958) has been determined to a resolution of 2.8 Angstrom using anomalous diffraction data at the Se-peak wavelength. Structure determination revealed a mostly alpha-helical protein with a three-lobed shape. The three lobes or fingers delineate a central binding groove and additional grooves between lobes 1 and 3 and between lobes 2 and 3. For one of the molecules in the asymmetric unit, the central binding pocket was filled with a peptide from the uncleaved N-terminal affinity tag. The MPN555 structure has structural homology to two bacterial chaperone proteins: SurA and trigger factor from Escherichia coli. The structural data and the homology to other chaperone proteins suggests an involvement in protein folding as a molecular chaperone for MPN555.
利用在硒峰波长下的反常衍射数据，已确定来自肺炎支原体（gi|1673958）的假定蛋白MPN555的晶体结构，分辨率达到2.8埃。结构测定显示该蛋白主要为α螺旋结构，呈三叶形。这三个叶或指状结构勾勒出一个中央结合凹槽以及叶1和叶3之间、叶2和叶3之间的额外凹槽。对于不对称单元中的一个分子，中央结合口袋被来自未切割的N端亲和标签的肽所填充。MPN555结构与两种细菌伴侣蛋白具有结构同源性：大肠杆菌的SurA和触发因子。结构数据以及与其他伴侣蛋白的同源性表明，MPN555作为分子伴侣参与蛋白质折叠。
