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[attach]2618[/attach] , Z& @2 }. E$ ?# B9 H# x, VBuilding virus particles: Symmetry is key ( b1 g6 j# [( y. Y' j. f; J9 c( OWatson and Crick did more than discover DNA structure 9 I. C+ \/ o! H* v/ Z7 h0 CTheir seminal contribution to virology:6 l2 {4 f2 Q; [7 ]' ?4 T( L
- Identical protein subunits are distributed with helical symmetry for rod-shaped viruses / o* o) W5 H8 |$ ]- Platonic polyhedra symmetry for round viruses 5 G% R6 e5 g1 o# k! t ) `& d9 m; M0 T( f4 B* k# MThe symmetry rules are elegant in their simplicity，They provide rules for “self-assembly” 3 U5 j& }, n4 h9 ?Rule 1: Each subunit has ‘identical’ bonding contacts with its neighbors- s# m- w0 _% z5 [( Z w- e
- Repeated interaction of chemically complementary surfaces at the subunit8 s% {& f0 c3 M! B% K$ I
interfaces naturally leads to a symmetric arrangement 1 p( ?6 w5 O% t# p9 h( s' d- @) i- vRule 2: These bonding contacts are usually non-covalent: D4 Y: r. {# G
- Reversible; error-free assembly* v6 O4 @& ]# f3 X
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[attach]2617[/attach] + T c1 y E VHow can you make a round capsid from proteins with irregular shapes? % x( o W5 i0 I7 T( S$ Y• Clue 1: All round capsids have precise numbers of proteins; multiples4 Y. W" M" [4 m0 [
of 60 are common (60, 180, 240, 960)) H& t3 h0 h5 {$ C4 a: X+ J
• Clue 2: Spherical viruses come in many sizes, but capsid proteins are% d& v/ Q1 U9 E8 \2 i
20-60 kDa average 0 k5 | ]$ u6 g 4 w) ~% W. j f1 C Y2 C, |' D# W. e1 ?5 {& S# r$ f $ e! Y# L: Y/ g# y9 e8 g/ Y0 v2 N P- H
附 Vincent R. Racaniello教授简介" s8 ]/ Q/ p: E, q; K) I: ], t
Prof.Vincent R. Racaniello (born January 2, 1953 in Paterson, New Jersey) is a Higgins Professor in the Department of Microbiology and Immunology at Columbia University’s College of Physicians and Surgeons. He is one of four virologists who has recently authored Principles of Virology, a textbook used by many teaching virology to undergraduate, medical and graduate students. ) M+ c7 @( j+ ?2 v: M5 ^ As an esteemed member of the scientific community, Racaniello has received several awards including Irma T. Hirschl, Searle Scholars, Eli Lilly and NIH Merit. He has also been a Harvey Society Lecturer at Rockefeller University, the Hilleman Lecturer at the University of Chicago, and University Lecturer at Columbia University. Racaniello has served on the editorial boards of scientific journals, including the Journal of Virology, and is a community editor for the open access journal PLOS Pathogens. He also served as the 2015 president of the American Society for Virology." {& _4 j# c1 B. {8 C% F
- B( T# T) i0 z # c: s' C, [1 W" A3 T附 PPT下载地址：0 Q3 H# o; e( `8 V G4 s! M
