PDBsum entry 3ii2

DNA binding protein

PDB id: 3ii2

Contents

Protein chain

150 a.a.

Ligands

GOL

Metals

_HG ×2

_CL ×3

_NI ×3

Waters ×116

PDB id:

3ii2

Name:

DNA binding protein

Title:

Structure of orf157 from acidianus filamentous virus 1

Structure:

Putative uncharacterized protein. Chain: a. Synonym: orf157. Engineered: yes

Source:

Acidianus filamentous virus 1. Afv-1. Organism_taxid: 235266. Gene: afv1 orf157. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.00Å R-factor: 0.174 R-free: 0.237

Authors:

A.Goulet,S.Porciero,D.Prangishvili,H.Van Tilbeurgh,C.Cambillau, V.Campanacci

Key ref:

A.Goulet et al. (2010). ORF157 from the archaeal virus Acidianus filamentous virus 1 defines a new class of nuclease. J Virol, 84, 5025-5031. PubMed id: 20200253

Date:

31-Jul-09 Release date: 23-Mar-10

Supersedes:

2oq8

Protein chain

Q70LE6  (Y157_AFV1Y) -  Uncharacterized protein ORF157 from Acidianus filamentous virus 1 (isolate United States/Yellowstone)

Seq: 157 a.a.

Struc: 150 a.a.

Enzyme reactions

• Enzyme class: E.C.?

J Virol 84:5025-5031 (2010)

PubMed id: 20200253

ORF157 from the archaeal virus Acidianus filamentous virus 1 defines a new class of nuclease.

A.Goulet, M.Pina, P.Redder, D.Prangishvili, L.Vera, J.Lichière, N.Leulliot, H.van Tilbeurgh, M.Ortiz-Lombardia, V.Campanacci, C.Cambillau.

ABSTRACT

Acidianus filamentous virus 1 (AFV1) (Lipothrixviridae) is an enveloped filamentous virus that was characterized from a crenarchaeal host. It infects Acidianus species that thrive in the acidic hot springs (>85 degrees C and pH <3) of Yellowstone National Park, WY. The AFV1 20.8-kb, linear, double-stranded DNA genome encodes 40 putative open reading frames whose sequences generally show little similarity to other genes in the sequence databases. Because three-dimensional structures are more conserved than sequences and hence are more effective at revealing function, we set out to determine protein structures from putative AFV1 open reading frames (ORF). The crystal structure of ORF157 reveals an alpha+beta protein with a novel fold that remotely resembles the nucleotidyltransferase topology. In vitro, AFV1-157 displays a nuclease activity on linear double-stranded DNA. Alanine substitution mutations demonstrated that E86 is essential to catalysis. AFV1-157 represents a novel class of nuclease, but its exact role in vivo remains to be determined.