The 1.0 A resolution crystal structure of he branched-chain amino acid transporter substrate binding protein LivJ (construct 35–386) from Streptococcus pneumoniae str. Canada MDR_19A in complex with Isoleucine was determined by molecular replacement. The P21 asymmetric unit contains a single copy of the protein that is composed of two domains. The N-terminal domain spans residues 35–155 and residues 292–358 that fold into a parallel 5-stranded beta-sheet and 3 helices, and an antiparallel 2-stranded beta-sheet and 3 helices. The C-terminal domain encompasses residues 157–291 and residues 359–386. Isoleucine residue binds the protein at the interface of the two domains. The residue’s side chain is facing a hydrophobic pocket, whereas its main-chain charged atoms interact with polar residues of the protein. The N-terminal domain contains modified residue, N-dimethyl-lysine, at position 345 that is surface exposed and faces Asn342.