PDBsum entry 4g1u

Transport protein/hydrolase

PDB id: 4g1u

Contents

Protein chains

297 a.a.

262 a.a.

Ligands

PO4 ×2

PDB id:

4g1u

Name:

Transport protein/hydrolase

Title:

X-ray structure of the bacterial heme transporter hmuuv from yersinia pestis

Structure:

Hemin transport system permease protein hmuu. Chain: a, b. Engineered: yes. Hemin import atp-binding protein hmuv. Chain: c, d. Engineered: yes

Source:

Yersinia pestis. Organism_taxid: 632. Gene: hmuu, ypo0280, y0540, yp_0435. Expressed in: escherichia coli. Expression_system_taxid: 562. Gene: hmuv, ypo0279, y0539, yp_0434.

Resolution:

3.01Å R-factor: 0.265 R-free: 0.295

Authors:

J.-S.Woo,B.A.Goetz,A.Zeltina,K.P.Locher

Key ref:

J.S.Woo et al. (2012). X-ray structure of the Yersinia pestis heme transporter HmuUV. Nat Struct Biol, 19, 1310-1315. PubMed id: 23142986

Date:

11-Jul-12 Release date: 19-Dec-12

Protein chains

Q56992  (HMUU_YERPE) -  Hemin transport system permease protein HmuU from Yersinia pestis

Seq: 334 a.a.

Struc: 297 a.a.

Protein chains

Q56993  (HMUV_YERPE) -  Hemin import ATP-binding protein HmuV from Yersinia pestis

Seq: 266 a.a.

Struc: 262 a.a.

Enzyme reactions

• Enzyme class 2: Chains A, B: E.C.?
• Enzyme class 3: Chains C, D: E.C.7.6.2.- - ?????

Note, where more than one E.C. class is given (as above), each may correspond to a different protein domain or, in the case of polyprotein precursors, to a different mature protein.

Nat Struct Biol 19:1310-1315 (2012)

PubMed id: 23142986

X-ray structure of the Yersinia pestis heme transporter HmuUV.

J.S.Woo, A.Zeltina, B.A.Goetz, K.P.Locher.

ABSTRACT

HmuUV is a bacterial ATP-binding cassette (ABC) transporter that catalyzes heme uptake into the cytoplasm of the Gram-negative pathogen Yersinia pestis. We report the crystal structure of HmuUV at 3.0 Å resolution in a nucleotide-free state, which features a heme translocation pathway in an outward-facing conformation, poised to accept a heme from the cognate periplasmic binding protein HmuT. A new assay allowed us to determine in vitro rates of HmuUV-catalyzed heme transport into proteoliposomes and to establish the role of conserved residues in the translocation pathway of HmuUV and at the interface with HmuT. Differences in architecture relative to the related vitamin B(12) transporter BtuCD suggest an adaptation of HmuUV for its smaller substrate. Our study also suggests that type II ABC importers, which include bacterial iron-siderophore, heme and cobalamin transporters, have a coupling mechanism distinct from that of other ABC transporters.