Jung Hyo-Il, Perham Richard N
Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK.
FEBS Lett. 2003 Dec 4;555(2):405-10. doi: 10.1016/s0014-5793(03)01245-6.
The beta-subunit (E1beta) of the pyruvate decarboxylase (E1, alpha(2)beta(2)) component of the Bacillus stearothermophilus pyruvate dehydrogenase complex was comparatively modelled based on the crystal structures of the homologous 2-oxoisovalerate decarboxylase of Pseudomonas putida and Homo sapiens. Based on this homology modelling, alanine-scanning mutagenesis studies revealed that the negatively charged side chain of Glu285 and the hydrophobic side chain of Phe324 are of particular importance in the interaction with the peripheral subunit-binding domain of the dihydrolipoyl acetyltransferase component of the complex. These results help to identify the site of interaction on the E1beta subunit and are consistent with thermodynamic evidence of a mixture of electrostatic and hydrophobic interactions being involved.
基于嗜热脂肪芽孢杆菌丙酮酸脱氢酶复合体中丙酮酸脱羧酶（E1，α₂β₂）组分的β亚基（E1β）与恶臭假单胞菌和智人的同源2-氧代异戊酸脱羧酶的晶体结构，对其进行了比较建模。基于此同源建模，丙氨酸扫描诱变研究表明，Glu285的带负电荷侧链和Phe324的疏水侧链在与复合体中二氢硫辛酰乙酰转移酶组分的外周亚基结合结构域的相互作用中尤为重要。这些结果有助于确定E1β亚基上的相互作用位点，并且与涉及静电和疏水相互作用混合物的热力学证据一致。
