PDBsum entry 3vvd

Transport protein

PDB id: 3vvd

Contents

Protein chains

241 a.a.

Ligands

ORN ×2

Waters ×300

PDB id:

3vvd

Name:

Transport protein

Title:

Crystal structure of ttc0807 complexed with ornithine

Structure:

Amino acid abc transporter, binding protein. Chain: a, b. Fragment: unp residues 19-254. Engineered: yes

Source:

Thermus thermophilus. Organism_taxid: 262724. Strain: hb27 / atcc baa-163 / dsm 7039. Gene: ttc0807, tt_c0807. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.05Å R-factor: 0.202 R-free: 0.249

Authors:

T.Tomita,Y.Kanemaru,F.Hasebe,T.Kuzuyama,M.Nishiyama

Key ref:

Y.Kanemaru et al. (2013). Two ATP-binding cassette transporters involved in (S)-2-aminoethyl-cysteine uptake in thermus thermophilus. J Bacteriol, 195, 3845-3853. PubMed id: 23794618 DOI: 10.1128/JB.00202-13

Date:

21-Jul-12 Release date: 26-Jun-13

Protein chains

Q72JG5  (Q72JG5_THET2) -  Amino acid ABC transporter, binding protein from Thermus thermophilus (strain ATCC BAA-163 / DSM 7039 / HB27)

Seq: 254 a.a.

Struc: 241 a.a.*

* PDB and UniProt seqs differ at 4 residue positions (black crosses)

DOI no: 10.1128/JB.00202-13

J Bacteriol 195:3845-3853 (2013)

PubMed id: 23794618

Two ATP-binding cassette transporters involved in (S)-2-aminoethyl-cysteine uptake in thermus thermophilus.

Y.Kanemaru, F.Hasebe, T.Tomita, T.Kuzuyama, M.Nishiyama.

ABSTRACT

Thermus thermophilus exhibits hypersensitivity to a lysine analog, (S)-2-aminoethyl-cysteine (AEC). Cosmid libraries were constructed using genomes from two AEC-resistant mutants, AT10 and AT14, and the cosmids that conferred AEC resistance on the wild-type strain were isolated. When the cosmid library for mutant AT14 was screened, two independent cosmids, conferring partial AEC resistance to the wild type, were obtained. Two cosmids carried a common genomic region from TTC0795 to TTC0810. This region contains genes encoding an ATP-binding cassette (ABC) transporter consisting of TTC0806/TTC0795, using TTC0807 as the periplasmic substrate-binding protein. Sequencing revealed that AT14 carries mutations in TTC0795 and TTC0969, causing decreases in the thermostability of the products. TTC0969 encodes the nucleotide-binding protein of a different ABC transporter consisting of TTC0967/TTC0968/TTC0969/TTC0970 using TTC0966 as the periplasmic substrate-binding protein. By similar screening for cosmids constructed for the mutant AT10, mutations were found at TTC0807 and TTC0969. Mutation in either of the transporter components gave partial resistance to AEC in the wild-type strain, while mutations of both transporters conferred complete AEC resistance. This result indicates that both transporters are involved in AEC uptake in T. thermophilus. To elucidate the mechanism of AEC uptake, crystal structures of TTC0807 were determined in several substrate-binding forms. The structures revealed that TTC0807 recognizes various basic amino acids by changing the side-chain conformation of Glu19, which interacts with the side-chain amino groups of the substrates.