Crystal structure of Streptococcus suis SuiB

Structures of the peptide-modifying radical SAM enzyme SuiB elucidate the basis of substrate recognition.

MGSSHHHHHHSSGLVPRGSHMRTISEDILFRLEKFGGILINKTNFERIELDETEAFFLYLVQNHGIEIATSFFKKEIEMG
KLERALSLNIYSDNNIEDSLNNPYETLQNARKHVAKLKKHNILSFPLELVIYPSMYCDLKCGFCFLANREDRNAKPAKDW
ERILRQAKDNGVLSVSILGGEPTRYFDIDNLLIACEELKIKTTITTNAQLIKKSTVEILAKSKYITPVLSLQTLDSKLNF
ELMGVRPDRQIKLAKYFNEVGKKCRINAVYTKQSYEQIIELVDFCIENKIDRFSVANYSEVTGYTKIKKKYDLADLRRLN
EYVTDYITQREANLNFATEGCHLFTAYPELINNSIEFSEFDEMYYGCRAKYTKMEIMSNGDILPCIAFLGVNQTKQNAFE
KDLLDVWYDDPLYGGIRSFRTKNSKCLSCGLLKICEGGCYVNLIKEKSPEYFRDSVCQL

A solution containing 18.9 mg/mL His6-tagged SuiB in storage buffer [100 mM HEPES, pH 7.5, 300 mM KCl, 5 mM DTT, 10% (v/v) glycerol] was mixed 1:1 with precipitant solution. Small clusters of crystals were formed within 24 hrs. A seed stock was then produced by combining a single sitting well with 10 uL of reservoir solution and 10 uL of enzyme at 8 mg/mL, followed by brief vortexing. A resulting crystal was harvested 2 days following seeding. The precipitant solution was 100 mM MES, pH 6.0, 15% (w/v) PEG 3350.

INITIAL DATASET USED FOR ANOMALOUS PHASING FROM IRON ATOMS COLLECTED AT 1.7369 A.

Radical SAM enzyme, Lys-Trp crosslink, Streptococcus suis, metalloenzyme, SPASM domain, RRE domain, METAL BINDING PROTEIN

MRTISEDILFRLEKFGGILINKTNFERIELDETEAFFLYLVQNHGIEIATSFFKKEIEMGKLERALSLNIYSDNNIEDSL
NNPYETLQNARKHVAKLKKHNILSFPLELVIYPSMYCDLKCGFCFLANREDRNAKPAKDWERILRQAKDNGVLSVSILGG
EPTRYFDIDNLLIACEELKIKTTITTNAQLIKKSTVEILAKSKYITPVLSLQTLDSKLNFELMGVRPDRQIKLAKYFNEV
GKKCRINAVYTKQSYEQIIELVDFCIENKIDRFSVANYSEVTGYTKIKKKYDLADLRRLNEYVTDYITQREANLNFATEG
CHLFTAYPELINNSIEFSEFDEMYYGCRAKYTKMEIMSNGDILPCIAFLGVNQTKQNAFEKDLLDVWYDDPLYGGIRSFR
TKNSKCLSCGLLKICEGGCYVNLIKEKSPEYFRDSVCQL