Membrane Protein Insertase Yidc (yidC) Escherichia Coli Recombinant Protein

Function: Inner membrane protein required for the insertion and/or proper folding and/or complex formation of integral inner membrane proteins. Involved in integration of membrane proteins that insert dependently and independently of the Sec translocase complex, as well as at least 2 lipoproteins. Its own insertion requires SRP and is Sec translocase-dependent. Essential for the integration of Sec-dependent subunit a of the F0ATP synthase, FtsQ and SecE proteins and for Sec-independent subunit c of the F0ATP synthase, M13 phage procoat and the N-terminus of leader peptidase Lep. Probably interacts directly with Sec-independent substrates. Sec-dependent protein FtsQ interacts first with SecY then subsequently with YidC. Sec-dependent LacY and MalF require YidC to acquire tertiary structure and stability, a chaperone-like function, but not for membrane insertion. Stable maltose transport copmplex formation (MalFGK2) also requires YidC. Partially complements a Streptococcus mutans yidC2 disruption mutant. Ref.6 Ref.7 Ref.11 Ref.14 Ref.15 Ref.16 Ref.18 Ref.21

Subunit structure: Interacts with SecD and SecF. Component of the SecDFyajC complex, a heterotetrameric translocase complex. Specifically interacts with transmembrane segments of nascent integral membrane proteins during membrane integration. Found in 3 different complexes in inner membrane preparations (Ref.17). Can be cross-linked to FtsH, in the larger FtsH/HflKC complex. Ref.6 Ref.8 Ref.10 Ref.14 Ref.17 Ref.19

Subcellular location: Cell inner membrane; Multi-pass membrane protein. Note: Predominantly localized at cell poles at all stages of cell growth. Ref.9 Ref.17

Induction: At mid-exponential phase in strain MC4100 there are about 2500 copies per cell (at protein level). HAMAP-Rule MF_01810

Domain: Most of the large periplasmic domain (residues 24-264) is not required for either Sec-dependent or Sec-independent protein insertion. However, residues 265-346, the C-terminal part of the large periplasmic domain, are required for both Sec-dependent and Sec-independent protein insertion. Ref.18

Disruption phenotype: Lethality. Upon depletion experiments insertion of Sec translocase-independent integral membrane proteins ceases. Translocation of Sec-dependent protein decreases to a lesser extent. Also leads to decreased targeting and/or translocation of Lpp and BRP lipoproteins. Both spoIIIJ and yqjG of B.subtilis functionally complement yidC depletion, whereas Streptococcus mutans yidC1 and yidC2 only partially complement depletion. Ref.7 Ref.8 Ref.16

Sequence similarities: Belongs to the OXA1/ALB3/YidC family. Type 1 subfamily.