PDBsum entry 4ffb

Hydrolase

PDB id: 4ffb

Contents

Protein chains

435 a.a.

421 a.a.

231 a.a.

Ligands

GTP ×2

Metals

_MG ×2

PDB id:

4ffb

Name:

Hydrolase

Title:

A tog:alpha/beta-tubulin complex structure reveals conformation-based mechanisms for a microtubule polymerase

Structure:

Tubulin alpha-1 chain. Chain: a. Engineered: yes. Tubulin beta chain. Chain: b. Synonym: beta-tubulin. Engineered: yes. Mutation: yes. Protein stu2.

Source:

Saccharomyces cerevisiae. Baker's yeast. Organism_taxid: 559292. Strain: atcc 204508 / s288c. Gene: tub1, yml085c. Expressed in: saccharomyces cerevisiae. Expression_system_taxid: 4932. Gene: tub2, yfl037w. Gene: l2108, stu2, ylr045c.

Resolution:

2.88Å R-factor: 0.210 R-free: 0.267

Authors:

P.Ayaz,X.Ye,P.Huddleston,C.A.Brautigam,L.M.Rice

Key ref:

P.Ayaz et al. (2012). A TOG:αβ-tubulin complex structure reveals conformation-based mechanisms for a microtubule polymerase. Science, 337, 857-860. PubMed id: 22904013

Date:

31-May-12 Release date: 15-Aug-12

Protein chain

P09733  (TBA1_YEAST) -  Tubulin alpha-1 chain from Saccharomyces cerevisiae (strain ATCC 204508 / S288c)

Seq: 447 a.a.

Struc: 435 a.a.

Protein chain

P02557  (TBB_YEAST) -  Tubulin beta chain from Saccharomyces cerevisiae (strain ATCC 204508 / S288c)

Seq: 457 a.a.

Struc: 421 a.a.*

Protein chain

P46675  (STU2_YEAST) -  Protein STU2 from Saccharomyces cerevisiae (strain ATCC 204508 / S288c)

Seq: 888 a.a.

Struc: 231 a.a.

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class 1: Chain A: E.C.3.6.5.- - ?????
• Enzyme class 2: Chain B: E.C.3.6.5.6 - tubulin GTPase.
• Reaction: GTP + H2O = GDP + phosphate + H⁺

GTP (Bound ligand (Het Group name = GTP) corresponds exactly) + H2O = GDP + phosphate + H(+)

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.

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

reference

Science 337:857-860 (2012)

PubMed id: 22904013

A TOG:αβ-tubulin complex structure reveals conformation-based mechanisms for a microtubule polymerase.

P.Ayaz, X.Ye, P.Huddleston, C.A.Brautigam, L.M.Rice.

ABSTRACT

Stu2p/XMAP215/Dis1 family proteins are evolutionarily conserved regulatory factors that use αβ-tubulin-interacting tumor overexpressed gene (TOG) domains to catalyze fast microtubule growth. Catalysis requires that these polymerases discriminate between unpolymerized and polymerized forms of αβ-tubulin, but the mechanism by which they do so has remained unclear. Here, we report the structure of the TOG1 domain from Stu2p bound to yeast αβ-tubulin. TOG1 binds αβ-tubulin in a way that excludes equivalent binding of a second TOG domain. Furthermore, TOG1 preferentially binds a curved conformation of αβ-tubulin that cannot be incorporated into microtubules, contacting α- and β-tubulin surfaces that do not participate in microtubule assembly. Conformation-selective interactions with αβ-tubulin explain how TOG-containing polymerases discriminate between unpolymerized and polymerized forms of αβ-tubulin and how they selectively recognize the growing end of the microtubule.