Characterization of the spasmin 1 gene in Zoothamnium arbuscula strain Kawagoe (protozoa, ciliophora) and its relation to other spasmins and centrins

Takeshi Itabashi, Kazuyuki Mikami, Hiroshi Asai

    Research output: Contribution to journalArticle

    8 Citations (Scopus)

    Abstract

    Zoothamnium arbuscula strain Kawagoe is a giant sessile peritrich ciliated protozoa that possesses a contractile organelle called a spasmoneme. We report here on the molecular characterization and provide an opportunity to discuss the evolutionary relationships of the Z. arbuscula spasmin; spasmins belong to the calmodulin superfamily and are the major components of spasmoneme filaments. We analysed and obtained the whole sequence of the spasmin 1 gene and a partial sequence of the spasmin 2 gene. It is surprising that the sequence of spasmin 1 does not contain introns and encodes an open reading frame of 531 bp. It predicts a product of 177 amino acids with a calculated molecular mass of 19659 Da and a pI of 4.68. The amino acid sequence has two putative calcium-binding domains. One of them is a functional domain, as defined by the EF-hand consensus. The varieties of spasmins were revealed by comparison with amino acid components and molecular relationships of spasmin 1 protein and other spasmins. A comparison of the amino acid sequence between the Z. arbuscula spasmin and known centrins indicates that spasmins have a one residue deletion in the EF-hand domain-2 and four residue insertions in domain-4, as does the Vorticella spasmin. However, there are large variations in the amino acid sequence at domain-4 within spasmin 1, spasmin 2 and the Vorticella spasmin.

    Original languageEnglish
    Pages (from-to)361-367
    Number of pages7
    JournalResearch in Microbiology
    Volume154
    Issue number5
    DOIs
    Publication statusPublished - 2003 Jun

    Keywords

    • Calcium-binding protein
    • Centrin
    • Ciliated protozoa
    • Evolution
    • Spasmin

    ASJC Scopus subject areas

    • Applied Microbiology and Biotechnology
    • Microbiology

    Fingerprint Dive into the research topics of 'Characterization of the spasmin 1 gene in Zoothamnium arbuscula strain Kawagoe (protozoa, ciliophora) and its relation to other spasmins and centrins'. Together they form a unique fingerprint.

  • Cite this