3QUW: Crystal Structure Of Yeast Mmf1

The yeast Saccharomyces cerevisiae mitochondrial matrix factor Mmf1, a member in the YER057c/Yigf/Uk114 family, participates in isoleucine biosynthesis and mitochondria maintenance. Mmf1 physically interacts with another mitochondrial matrix protein Mam33, which is involved in the sorting of cytochrome b(2) to the intermembrane space as well as mitochondrial ribosomal protein synthesis. To elucidate the structural basis for their interaction, we determined the crystal structures of Mmf1 and Mam33 at 1.74 and 2.10A, respectively. Both Mmf1 and Mam33 adopt a trimeric structure: each subunit of Mmf1 displays a chorismate mutase fold with a six-stranded beta-sheet flanked by two alpha-helices on one side, whereas a subunit of Mam33 consists of a twisted six-stranded beta-sheet surrounded by five alpha-helices. Biochemical assays combined with structure-based computational simulation enable us to model a putative complex of Mmf1-Mam33, which consists of one Mam33 trimer and two tandem Mmf1 trimers in a head-to-tail manner. The two interfaces between the ring-like trimers are mainly composed of electrostatic interactions mediated by complementary negatively and positively charged patches. These results provided the structural insights into the putative function of Mmf1 during mitochondrial protein synthesis via Mam33, a protein binding to mitochondrial ribosomal proteins.
PDB ID: 3QUWDownload
MMDB ID: 91227
PDB Deposition Date: 2011/2/24
Updated in MMDB: 2011/08
Experimental Method:
x-ray diffraction
Resolution: 1.75  Å
Source Organism:
Similar Structures:
Biological Unit for 3QUW: trimeric; determined by author and by software (PISA)
Molecular Components in 3QUW
Label Count Molecule
Proteins (3 molecules)
Protein Mmf1(Gene symbol: MMF1)
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB