Structure of the S. cerevisiae Srs2 C-terminal domain in complex with PCNA conjugated to SUMO on lysine 164

Recognition of SUMO-modified PCNA requires tandem receptor motifs in Srs2.

GSH from N-tag after thrombin cleavage, K19R

1.9 M AMMONIUM SULFATE
4% PEG 400
100 mM HEPES, pH 7.5, VAPOR DIFFUSION, HANGING DROP, temperature 279K

THERE IS AN ISOPEPTIDE LINKAGE BETWEEN RESIDUES A98 AND B164; D98 AND E164

NEM molecule has occupancy of 1 as mass spec suggested that this ligand is fully modified in the studied samples.

Ubiquitin-like protein SMT3, Proliferating cell nuclear antigen, ATP-dependent DNA helicase SRS2 (E.C.3.6.4.12)

PCNA IS NORMALLY A TRIMER BUT NEM MODIFICATION DISRUPTS THE TRIMER AND CAUSES PCNA TO RUN AS A MONOMER ON GEL FILTRATION THIS SUMO-PCNA MONOMER CRYSTALLIZES BY REFORMING THE PCNA:PCNA PROTOMER BUT WITH A RIGHT HANDED HELICAL SCREW COMPOSED OF 4 SUBUNITS THE ASU HAS 2 AND THE UNIT CELL CONTAINS ONE TURN OF THIS HELICAL SCREW WITH 4 PROTOMERS

UBIQUITIN-LIKE PROTEIN PCNA, POST-TRANSLATIONAL MODIFICATION DNA REPLICATION DNA DAMAGE RESPONSE, SRS2, NEM MODIFICATION ON PCNA CYS22 AND CYS81 REDUCTIVE METHYLATION OF ALL LYSINE RESIDUES ON SMT3, NUCLEAR, PROTEIN BINDING-DNA BINDING PROTEIN complex