5HM4

Crystal structure of oligopeptide ABC transporter, periplasmic oligopeptide-binding protein (TM1226) from THERMOTOGA MARITIMA at 2.0 A resolution

Summary for 5HM4

• Entry DOI: 10.2210/pdb5hm4/pdb
• Related: 4PFU 4PFW
• Descriptor: Mannoside ABC transport system, sugar-binding protein, CALCIUM ION (3 entities in total)
• Functional Keywords: abc transporter, transport protein
• Biological source: Thermotoga maritima
• Total number of polymer chains: 1
• Total formula weight: 63875.21

Authors

Lu, X.,Ghimire-Rijal, S.,Myles, D.A.A.,Cuneo, M.J. (deposition date: 2016-01-15, release date: 2016-11-23, Last modification date: 2024-01-10)

Primary citation

Li, L.,Ghimire-Rijal, S.,Lucas, S.L.,Stanley, C.B.,Wright, E.,Agarwal, P.K.,Myles, D.A.,Cuneo, M.J.
Periplasmic Binding Protein Dimer Has a Second Allosteric Event Tied to Ligand Binding.
Biochemistry, 56:5328-5337, 2017

PubMed Abstract: The ligand-induced conformational changes of periplasmic binding proteins (PBP) play a key role in the acquisition of metabolites in ATP binding cassette (ABC) transport systems. This conformational change allows for differential recognition of the ligand occupancy of the PBP by the ABC transporter. This minimizes futile ATP hydrolysis in the transporter, a phenomenon in which ATP hydrolysis is not coupled to metabolite transport. In many systems, the PBP conformational change is insufficient at eliminating futile ATP hydrolysis. Here we identify an additional state of the PBP that is also allosterically regulated by the ligand. Ligand binding to the homodimeric apo PBP leads to a tightening of the interface α-helices so that the hydrogen bonding pattern shifts to that of a 3 helix, in-turn altering the contacts and the dynamics of the protein interface so that the monomer exists in the presence of ligand.

PubMed: 28876049
DOI: 10.1021/acs.biochem.7b00657

Experimental method

X-RAY DIFFRACTION (2 Å)