119th General Meeting of the KCS

Type Poster Presentation
Area 생명화학
Room No. 포스터발표장
Time 4월 21일 (금요일) 13:00~14:30
Code BIO.P-283
Subject Comparison of Type I and Type II Acyl Carrier Protein using NMR Spectroscopy
Authors 양근상, 이영준1, 김양미*
건국대학교 생명공학과, Korea
1건국대학교 생명특성화대학, Korea
Abstract The synthases of Type I FAS are arranged as large multi-domain polypeptides. Acyl Carrier protein (ACP) is an acidic protein which is essential for fatty acid synthesis (FAS). In this work, Type I Human ACP and S. coelicolor ACPS were cloned, expressed, and purified. CD spectra of Human ACP showed double minima at 205 and 222 nm, which are characteristic of an α-helical structure. We performed multi-dimensional heteronuclear NMR experiments on 15N and 13C labeled protein and completed the backbone assignment. Chemical Shift Index showed that Human ACP has four α-helices, showing that α1 and α4 are relatively shorter compared to those of bacterial ACPs. Chemical shift perturbations upon conversion of the apo to the holo ACP, and octanoyl ACP revealed that Human ACP does not sequester growing acyl chain in the hydrophobic pocket. The hydrophobic triad residues in human ACP blocks the entrance to a hydrophobic pocket. The melting temperature of Human ACP is much higher compared to that of E.coli ACP and it was more stable in the absence of metal ion. Human ACP has more positively charged residues compared to bacterial ACPs which reduced the electrostatic repulsions. Since charge distribution of Type II FAS is different from that of Type I FAS, this makes bacterial FAS proteins as attractive targets for development of potent antibiotics.
E-mail yangks95@konkuk.ac.kr