Mechanosensitive Channel of Large Conductance (MscL)

Structures of the Prokaryotic Mechanosensitive Channels MscL and MscS

Structure of the MscL homolog from Mycobacterium tuberculosis: A gated mechanosensitive ion channel

METHODS AND RESULTS IN CRYSTALLIZATION OF MEMBRANE PROTEINS
Crystallization and structure determination of MSCL, a gated prokaryotic mechanosensitive channel

Large-conductance mechanosensitive channel

MGHHHHHHHHHHSSGHIDDDDKHMLKGFKEFLARGNIVDLAVAVVIGTAFTALVTKFTDSIITPLINRIGVNAQSDVGIL
RIGIGGGQTIDLNVLLSAAINFFLIAFAVYFLVVLPYNTLRKKGEVEQPGDTQVVLLTEIRDLLAQTNGDSPGRHGGRGT
PSPTDGPRASTESQ

PROTEIN CONCENTRATION 15-20 MG/ML AND 0.05% DODECYLMALTOSIDE.PROTEIN WAS MIXED IN A RATIO OF 4:3 OR 3:2 WITH THE RESERVOIR SOLUTION CONTAINING 100-120 mM AMMONIUM SULFUATE, 23-27% TRIETHYLENE GLYCOL, 100 mM GLYCINE, WITH 1-3 mM GD(CL)3 OR SM(CL)3 AND D2O AS THE SOLVENT. 1 mM (NA3)AU(S2O3)2 WAS SOAKED INTO THE CRYSTAL, pH 3.7, VAPOR DIFFUSION, SITTING DROP

SEQUENCE
All the non-histidine residues in the N-terminal 22
residues are part of a cleavable his-tag construct that
was added to the MscL sequence. The protein sequence is
not cleaved

The asymmetric unit contains one pentamer which is the biological unit

stretch activated ion channel mechanosensitive, MEMBRANE PROTEIN

MLKGFKEFLARGNIVDLAVAVVIGTAFTALVTKFTDSIITPLINRIGVNAQSDVGILRIGIGGGQTIDLNVLLSAAINFF
LIAFAVYFLVVLPYNTLRKKGEVEQPGDTQVVLLTEIRDLLAQTNGDSPGRHGGRGTPSPTDGPRASTESQ