AScI Talks, Speaker Dr. Weitao Sun (Tsinghua University, China)

Welcome to AScI Talks!

Time: Wednesday 18^th February at 14:15

Place: TUAS building, Otaniementie 17, AScI premises 3rd floor, use the elevator in the TUAS lounge to AScI lounge 3161 (street side open office space)

Speaker: Dr. Weitao Sun (Tsinghua University, China)

Title: From cluster to network: can residue organization help to understand protein function

Abstract: Residue clusters play essential role in stabilizing protein structures in the form of a complex network. The cluster size and local clustering coefficient are fundamental in describing both residue nucleation and cluster cliquishness in residue contact network. Considering the conformation anisotropy, atom distance criteria method is developed for determination of residue sidechain contact. It is shown that the residue cluster sizes in native protein are log-normal distributed. Based on the analysis of 424 PDBs, A critical protein size is observed from the asymptotically increasing mean cluster size vs. protein chain length data. Above the critical size, protein structures are considered as tightly packed. The power-law distributions of contact degree in current PDB database reveal that residue clusters form scale-free network, except for some extremely tightly packed proteins. Residue cluster network wheel (RCNW) is proposed to study the hierarchy and residue interaction potential energy in cluster contact networks. The heterogeneous distributions of intra/inter residue cluster potential energy suggest that protein structure stability is a compromise of residue interactions, which is essential for understanding the rate of protein folding.We find a way to partition residue networks into community structure. 1/3 catalytic sites are shared by different communities, which suggests that protein catalytic dynamics may be determined by community coordinations.

AScI Talks Seminar presentations idea is to give a short (max 30 min) talk, which is accessible to audience from different disciplines. The event is open to everyone and no registration is required.