Characterization of a Gene Family Encoding SEA (Sea-urchin Sperm Protein, Enterokinase and Agrin)-Domain Proteins with Lectin-Like and Heme-Binding Properties from Schistosoma japonicum

DOI 機関リポジトリ 機関リポジトリ 機関リポジトリ (HANDLE) 機関リポジトリ (HANDLE) ほか2件をすべて表示 一部だけ表示

書誌事項

タイトル
Characterization of a Gene Family Encoding SEA (Sea-urchin Sperm Protein, Enterokinase and Agrin)-Domain Proteins with Lectin-Like and Heme-Binding Properties from Schistosoma japonicum
タイトル別名
  • 日本住血吸虫ゲノムにはレクチン様でヘム結合性のＳＥＡ（ウニ精子タンパク）ドメインを有する膜型あるいは分泌型のタンパクをコードする多重遺伝子族が存在する
著者
Mbanefo, Evaristus Chibunna
学位授与大学
Nagasaki University (長崎大学)
取得学位
博士(医学)
学位授与番号
甲医歯薬第656号
学位授与年月日
2014-03-20

この論文をさがす

説明

Background We previously identified a novel gene family dispersed in the genome of Schistosoma japonicum by retrotransposon-mediated gene duplication mechanism. Although many transcripts were identified, no homolog was readily identifiable from sequence information. Methodology/Principal Findings Here, we utilized structural homology modeling and biochemical methods to identify remote homologs, and characterized the gene products as SEA (sea-urchin sperm protein, enterokinase and agrin)-domain containing proteins. A common extracellular domain in this family was structurally similar to SEA-domain. SEA-domain is primarily a structural domain, known to assist or regulate binding to glycans. Recombinant proteins from three members of this gene family specifically interacted with glycosaminoglycans with high affinity, with potential implication in ligand acquisition and immune evasion. Similar approach was used to identify a heme-binding site on the SEA-domain. The heme-binding mode showed heme molecule inserted into a hydrophobic pocket, with heme iron putatively coordinated to two histidine axial ligands. Heme-binding properties were confirmed using biochemical assays and UV-visible absorption spectroscopy, which showed high affinity heme-binding (KD = 1.605×10?6 M) and cognate spectroscopic attributes of hexa-coordinated heme iron. The native proteins were oligomers, antigenic, and are localized on adult worm teguments and gastrodermis; major host-parasite interfaces and site for heme detoxification and acquisition. Conclusions The results suggest potential role, at least in the nucleation step of heme crystallization (hemozoin formation), and as receptors for heme uptake. Survival strategies exploited by parasites, including heme homeostasis mechanism in hemoparasites, are paramount for successful parasitism. Thus, assessing prospects for application in disease intervention is warranted.

目次

2021-03-07 再収集

詳細情報 詳細情報について

問題の指摘

ページトップへ