PDBsum entry 1dqc

Antimicrobial protein

PDB id: 1dqc

Contents

Protein chain

74 a.a. *

* Residue conservation analysis

PDB id:

1dqc

Name:

Antimicrobial protein

Title:

Solution structure of tachycitin, an antimicrobial protein with chitin-binding function

Structure:

Tachycitin. Chain: a

Source:

Tachypleus tridentatus. Organism_taxid: 6853. Cell: hemocyte

NMR struc:

25 models

Authors:

T.Suetake,S.Tsuda,S.Kawabata,K.Miura,K.Kawano

Key ref:

T.Suetake et al. (2000). Chitin-binding proteins in invertebrates and plants comprise a common chitin-binding structural motif. J Biol Chem, 275, 17929-17932. PubMed id: 10770921 DOI: 10.1074/jbc.C000184200

Date:

04-Jan-00 Release date: 13-Sep-00

Protein chain

P91818  (P91818_TACTR) -  Tachycitin from Tachypleus tridentatus

Seq: 98 a.a.

Struc: 74 a.a.*

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

DOI no: 10.1074/jbc.C000184200

J Biol Chem 275:17929-17932 (2000)

PubMed id: 10770921

Chitin-binding proteins in invertebrates and plants comprise a common chitin-binding structural motif.

T.Suetake, S.Tsuda, S.Kawabata, K.Miura, S.Iwanaga, K.Hikichi, K.Nitta, K.Kawano.

ABSTRACT

Tachycitin, a 73-residue polypeptide having antimicrobial activity is present in the hemocyte of horseshoe crab (Tachypleus tridentatus). The first three-dimensional structure of invertebrate chitin-binding protein was determined for tachycitin using two-dimensional nuclear magnetic resonance spectroscopy. The measurements indicate that the structure of tachycitin is largely divided into N- and C-terminal domains; the former comprises a three-stranded beta-sheet and the latter a two-stranded beta-sheet following a short helical turn. The latter structural motif shares a significant tertiary structural similarity with the chitin-binding domain of plant chitin-binding protein. This result is thought to provide faithful experimental evidence to the recent hypothesis that chitin-binding proteins of invertebrates and plants are correlated by a convergent evolution process.

Selected figure(s)

Figure 1.
Fig. 1. Solution structure of tachycitin. A, stereo view of the best-fit superposition of 25 structures of tachycitin using backbone atoms (C^ , C, and N) of residues 6-68. B, ribbon representation of the minimized average structure of tachycitin. Disulfide bonds (yellow), -sheets (blue), and an helical turn (red) are indicated. Drawings were prepared using MOLMOL (26).

Figure 3.
Fig. 3. Putative chitin-binding site of tachycitin (Cys-40-Gly-60) superimposed onto the previously identified chitin-binding site of hevein (Cys-12-Ser-32). The conserved disulfide bonds are colored in green. Residues of Asn-47, Tyr-49, and Val-52 in the -hairpin of tachycitin (red) are superimposed onto the chitin-binding residues of hevein (blue).

The above figures are reprinted by permission from the ASBMB: J Biol Chem (2000, 275, 17929-17932) copyright 2000.

Figures were selected by an automated process.