Annotations: 8E1M

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
C	SCOP2B Superfamily	NTF2-like	8034007	3000472	SCOP2B (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
E [auth H]	RNA_pol_Rpb6	e8e1mH1	A: a/b three-layered sandwiches	X: RNase A-like	H: RNase A-like	T: RNase A-like	F: RNA_pol_Rpb6	ECOD (v294.1)
D [auth L]	RNA_pol_Rpb6	e8e1mL1	A: a/b three-layered sandwiches	X: RNase A-like	H: RNase A-like	T: RNase A-like	F: RNA_pol_Rpb6	ECOD (v294.1)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
E [auth H]	Heavy Chain	IGHV2	-	mitochondrial import inner membrane translocase subunittim44	SAbDab (2026-04-10)
D [auth L]	Light Chain	IGKV3	Kappa	mitochondrial import inner membrane translocase subunittim44	SAbDab (2026-04-10)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
C	PF04280	Tim44-like domain (Tim44)	Tim44-like domain	Tim44 is an essential component of the machinery that mediates the translocation of nuclear-encoded proteins across the mitochondrial inner membrane [1]. Tim44 is thought to bind phospholipids of the mitochondrial inner membrane both by electrostati ...	Tim44 is an essential component of the machinery that mediates the translocation of nuclear-encoded proteins across the mitochondrial inner membrane [1]. Tim44 is thought to bind phospholipids of the mitochondrial inner membrane both by electrostatic interactions and by penetrating the polar head group region [1]. This family includes the C-terminal region of Tim44 that has been shown to form a stable proteolytic fragment in yeast. This region is also found in a set of smaller bacterial proteins. The molecular function of the bacterial members of this family is unknown but transport seems likely. The crystal structure of the C terminal of Tim44 has revealed a large hydrophobic pocket which might play an important role in interacting with the acyl chains of lipid molecules in the mitochondrial membrane [3].	Domain
B	PF02466	Tim17/Tim22/Tim23/Pmp24 family (Tim17)	Tim17/Tim22/Tim23/Pmp24 family	-	Family
A	PF02466	Tim17/Tim22/Tim23/Pmp24 family (Tim17)	Tim17/Tim22/Tim23/Pmp24 family	-	Family

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
E [auth H]	Antibody Fab fragment heavy chain	-	-	-
D [auth L]	Antibody Fab fragment light chain	-	-	-
C	Mitochondrial import inner membrane translocase subunit TIM44	binding adenyl ribonucleotide binding nucleotide binding purine ribonucleotide binding purine ribonucleoside triphosphate binding nucleoside phosphate binding ion binding purine nucleotide binding anion binding adenyl nucleotide binding ATP binding heterocyclic compound binding carbohydrate derivative binding ribonucleotide binding binding adenyl ribonucleotide binding nucleotide binding purine ribonucleotide binding purine ribonucleoside triphosphate binding nucleoside phosphate binding ion binding purine nucleotide binding anion binding adenyl nucleotide binding ATP binding heterocyclic compound binding carbohydrate derivative binding ribonucleotide binding small molecule binding protein binding protein-folding chaperone binding protein-macromolecule adaptor activity molecular adaptor activity	cellular localization establishment of protein localization transport intracellular transport establishment of localization localization protein transport establishment of localization in cell macromolecule localization cellular process intracellular protein localization intracellular protein transport protein import into mitochondrial matrix transmembrane transport cellular localization establishment of protein localization transport intracellular transport establishment of localization localization protein transport establishment of localization in cell macromolecule localization cellular process intracellular protein localization intracellular protein transport protein import into mitochondrial matrix transmembrane transport intercellular transport establishment of protein localization to organelle protein transmembrane transport protein localization to organelle protein localization to mitochondrion	membrane-bounded organelle intracellular organelle cellular anatomical structure intracellular anatomical structure mitochondrion organelle cytoplasm intracellular membrane-bounded organelle mitochondrial membrane organelle inner membrane membrane mitochondrial inner membrane organelle envelope mitochondrial envelope membrane-bounded organelle intracellular organelle cellular anatomical structure intracellular anatomical structure mitochondrion organelle cytoplasm intracellular membrane-bounded organelle mitochondrial membrane organelle inner membrane membrane mitochondrial inner membrane organelle envelope mitochondrial envelope organelle membrane protein-containing complex TIM23 mitochondrial import inner membrane translocase complex membrane-enclosed lumen membrane protein complex PAM complex, Tim23 associated import motor mitochondrial matrix intracellular organelle lumen mitochondrial protein-containing complex inner mitochondrial membrane protein complex organelle lumen extrinsic component of organelle membrane extrinsic component of membrane extrinsic component of mitochondrial inner membrane
B	Mitochondrial import inner membrane translocase subunit TIM23	signal sequence binding binding peptide binding mitochondrion targeting sequence binding macromolecule transmembrane transporter activity protein transporter activity transmembrane protein transporter activity transporter activity transmembrane transporter activity	cellular localization establishment of protein localization transport intracellular transport establishment of localization localization protein transport establishment of localization in cell macromolecule localization cellular process intracellular protein localization intracellular protein transport protein insertion into mitochondrial membrane mitochondrial membrane organization cellular localization establishment of protein localization transport intracellular transport establishment of localization localization protein transport establishment of localization in cell macromolecule localization cellular process intracellular protein localization intracellular protein transport protein insertion into mitochondrial membrane mitochondrial membrane organization cellular component organization cellular component organization or biogenesis protein insertion into mitochondrial inner membrane protein insertion into membrane mitochondrion organization membrane organization establishment of protein localization to membrane inner mitochondrial membrane organization localization within membrane organelle organization establishment of protein localization to organelle protein localization to organelle protein localization to mitochondrion protein import into mitochondrial matrix transmembrane transport intercellular transport protein transmembrane transport	membrane-bounded organelle intracellular organelle cellular anatomical structure intracellular anatomical structure mitochondrion organelle cytoplasm intracellular membrane-bounded organelle mitochondrial membrane organelle inner membrane membrane mitochondrial inner membrane organelle envelope mitochondrial envelope membrane-bounded organelle intracellular organelle cellular anatomical structure intracellular anatomical structure mitochondrion organelle cytoplasm intracellular membrane-bounded organelle mitochondrial membrane organelle inner membrane membrane mitochondrial inner membrane organelle envelope mitochondrial envelope organelle membrane mitochondrial protein-containing complex protein-containing complex TIM23 mitochondrial import inner membrane translocase complex membrane protein complex inner mitochondrial membrane protein complex mitochondrial intermembrane space membrane-enclosed lumen intracellular organelle lumen organelle envelope lumen organelle lumen
A	Mitochondrial import inner membrane translocase subunit TIM17	macromolecule transmembrane transporter activity protein transporter activity transmembrane protein transporter activity transporter activity transmembrane transporter activity	cellular localization establishment of protein localization transport intracellular transport establishment of localization localization protein transport establishment of localization in cell macromolecule localization cellular process intracellular protein localization intracellular protein transport protein insertion into mitochondrial membrane mitochondrial membrane organization cellular localization establishment of protein localization transport intracellular transport establishment of localization localization protein transport establishment of localization in cell macromolecule localization cellular process intracellular protein localization intracellular protein transport protein insertion into mitochondrial membrane mitochondrial membrane organization cellular component organization cellular component organization or biogenesis protein insertion into mitochondrial inner membrane protein insertion into membrane mitochondrion organization membrane organization establishment of protein localization to membrane inner mitochondrial membrane organization localization within membrane organelle organization establishment of protein localization to organelle protein localization to organelle protein localization to mitochondrion protein import into mitochondrial matrix transmembrane transport intercellular transport protein transmembrane transport	membrane-bounded organelle intracellular organelle cellular anatomical structure intracellular anatomical structure mitochondrion organelle cytoplasm intracellular membrane-bounded organelle mitochondrial membrane organelle inner membrane membrane mitochondrial inner membrane organelle envelope mitochondrial envelope membrane-bounded organelle intracellular organelle cellular anatomical structure intracellular anatomical structure mitochondrion organelle cytoplasm intracellular membrane-bounded organelle mitochondrial membrane organelle inner membrane membrane mitochondrial inner membrane organelle envelope mitochondrial envelope organelle membrane mitochondrial protein-containing complex protein-containing complex TIM23 mitochondrial import inner membrane translocase complex membrane protein complex inner mitochondrial membrane protein complex mitochondrial intermembrane space membrane-enclosed lumen intracellular organelle lumen organelle envelope lumen organelle lumen

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
C	IPR032710	NTF2-like domain superfamily	Homologous Superfamily
C	IPR007379	Tim44-like domain	Domain
C	IPR039544	Tim44-like	Family
C	IPR017303	Mitochondrial import inner membrane translocase subunit Tim44	Family
B	IPR045238	Tim23-like	Family
B	IPR005681	Mitochondrial inner membrane translocase complex, subunit Tim23	Family
A	IPR005678	Mitochondrial inner membrane translocase complex, subunit Tim17	Family

Membrane Protein Annotation: PDBTM PDBTM Database Homepage

Chains	External Link	Comment
A, B, C	PDBTM	Annotated as membrane protein by PDBTM

Membrane Protein Annotation: mpstruc mpstruc Database Homepage

Chains	Resource Link	Group	Subgroup	Protein
A, B, C	mpstruc	TRANSMEMBRANE PROTEINS: ALPHA-HELICAL	Sec, Translocase, and Insertase Proteins	TIM23 complex (Tim17–Tim23–Tim44) from mitochondrial inner membrane

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729. RCSB PDB uses resources of the National Energy Research Scientific Computing Center (NERSC), a Department of Energy User Facility.