PDBsum entry 3qb8

Transferase

PDB id: 3qb8

Contents

Protein chains

197 a.a.

Ligands

COA ×2

IMD ×2

Waters ×417

PDB id:

3qb8

Name:

Transferase

Title:

Paramecium chlorella bursaria virus1 putative orf a654l is a polyamine acetyltransferase

Structure:

A654l protein. Chain: a, b. Engineered: yes

Source:

Paramecium bursaria chlorella virus 1. Pbcv-1. Organism_taxid: 10506. Gene: a654l. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Resolution:

1.50Å R-factor: 0.153 R-free: 0.168

Authors:

Z.Charlop-Powers,M.-M.Zhou,J.Jakoncic,J.Gurnon,J.Van Etten

Key ref:

Z.Charlop-Powers et al. (2012). Paramecium bursaria chlorella virus 1 encodes a polyamine acetyltransferase. J Biol Chem, 287, 9547-9551. PubMed id: 22277659

Date:

12-Jan-11 Release date: 25-Jan-12

Protein chains

O41136  (O41136_PBCV1) -  N-acetyltransferase domain-containing protein from Paramecium bursaria Chlorella virus 1

Seq: 197 a.a.

Struc: 197 a.a.

Enzyme reactions

• Enzyme class: E.C.?

J Biol Chem 287:9547-9551 (2012)

PubMed id: 22277659

Paramecium bursaria chlorella virus 1 encodes a polyamine acetyltransferase.

Z.Charlop-Powers, J.Jakoncic, J.R.Gurnon, J.L.Van Etten, M.M.Zhou.

ABSTRACT

Paramecium bursaria chlorella virus 1 (PBCV-1), a large DNA virus that infects green algae, encodes a histone H3 lysine 27-specific methyltransferase that functions in global transcriptional silencing of the host. PBCV-1 has another gene a654l that encodes a protein with sequence similarity to the GCN5 family histone acetyltransferases. In this study, we report a 1.5 Å crystal structure of PBCV-1 A654L in a complex with coenzyme A. The structure reveals a unique feature of A654L that precludes its acetylation of histone peptide substrates. We demonstrate that A654L, hence named viral polyamine acetyltransferase (vPAT), acetylates polyamines such as putrescine, spermidine, cadaverine, and homospermidine present in both PBCV-1 and its host through a reaction dependent upon a conserved glutamate 27. Our study suggests that as the first virally encoded polyamine acetyltransferase, vPAT plays a possible key role in the regulation of polyamine catabolism in the host during viral replication.