Cob(I)alamin (ECMDB04040) (M2MDB000574)

General function:

Involved in nucleotide binding

Specific function:

Part of the ABC transporter complex BtuCDF involved in vitamin B12 import. Responsible for energy coupling to the transport system

Gene Name:

btuD

Uniprot ID:

P06611

Molecular weight:

27081

Reactions

General function:

Involved in receptor activity

Specific function:

Involved in the active translocation of vitamin B12 (cyanocobalamin) across the outer membrane to the periplasmic space. It derives its energy for transport by interacting with the trans-periplasmic membrane protein tonB. Is also a receptor for bacteriophages BF23 and C1, and for A and E colicins

Gene Name:

btuB

Uniprot ID:

P06129

Molecular weight:

68407

General function:

Involved in cobalamin transport

Specific function:

Part of the ABC transporter complex BtuCDF involved in vitamin B12 import. Involved in the translocation of the substrate across the membrane

Gene Name:

btuC

Uniprot ID:

P06609

Molecular weight:

34949

General function:

Involved in binding

Specific function:

Part of the ABC transporter complex BtuCDF involved in vitamin B12 import. Binds vitamin B12 and delivers it to the periplasmic surface of BtuC

Gene Name:

btuF

Uniprot ID:

P37028

Molecular weight:

29367

General function:

Involved in protein transporter activity

Specific function:

Involved in the tonB-dependent energy-dependent transport of various receptor-bound substrates. Protects exbD from proteolytic degradation and functionally stabilizes tonB

Gene Name:

exbB

Uniprot ID:

P0ABU7

Molecular weight:

26287

General function:

Involved in transporter activity

Specific function:

Involved in the tonB-dependent energy-dependent transport of various receptor-bound substrates

Gene Name:

exbD

Uniprot ID:

P0ABV2

Molecular weight:

15527

General function:

Involved in iron ion transmembrane transporter activity

Specific function:

Interacts with outer membrane receptor proteins that carry out high-affinity binding and energy dependent uptake into the periplasmic space of specific substrates such as cobalamin, and various iron compounds (such as iron dicitrate, enterochelin, aerobactin, etc.). In the absence of tonB these receptors bind their substrates but do not carry out active transport. TonB also interacts with some colicins and is involved in the energy- dependent, irreversible steps of bacteriophages phi 80 and T1 infection. It could act to transduce energy from the cytoplasmic membrane to specific energy-requiring processes in the outer membrane, resulting in the release into the periplasm of ligands bound by these outer membrane proteins

Gene Name:

tonB

Uniprot ID:

P02929

Molecular weight:

26094