title: An N-acetyllactosamine-specific lectin, PFA, isolated from a moth (Phalera flavescens), structurally resembles an invertebrate-type lysozyme.
abstract: PFA (Phalera flavescens agglutinin) lectin purified from larvae of the lobster moth (P. flavescens) shows a strong binding ability specific to the N-acetyllactosamine (Galβ1-4GlcNAc) site. We determined the genomic and cDNA sequences of the PFA gene, which consists of five exons and spans approximately 5 kb of a genomic region. Surprisingly, the amino acid sequence (149 amino acids) was similar to invertebrate-type lysozymes and related proteins. The predicted tertiary structure of the PFA protein was similar to the lysozymes of clams such as the common orient clam (Meretrix lusoria) and Japanese littleneck (Venerupis philippinarum (Tapes japonica)). The PFA, however, lacks a catalytically essential amino acid, an Asp (D), which is one of the two important amino acids (Glu (E) and D) express the function of lysozyme. As a result, lysozyme activity assays indicated that PFA does not have lysozyme activity. Results suggest that the PFA gene evolved from a lysozyme gene through the loss of lysozyme activity sites and the acquisition of lectin activity during evolution of the genus Phalera.
authors.affiliation: Department of Biomolecular Functional Engineering, College of Engineering, Ibaraki University, 4-12-1 Nakanarusawa-cho, Hitachi 316-8511, Japan.
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Yokoyama
authors.affiliation: Technical Support Center of Education and Research, Yamagata University School of Medicine, 2-2-2 Iidanishi, Yamagata 990-9585, Japan.
authors.forename: Michihiko
authors.initials: M
authors.lastname: Sato
authors.affiliation: Department of Forensic Medicine, Yamagata University School of Medicine, 2-2-2 Iidanishi, Yamagata 990-9585, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Haneda
authors.affiliation: Department of Forensic Medicine, Yamagata University School of Medicine, 2-2-2 Iidanishi, Yamagata 990-9585, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yamazaki
authors.affiliation: Department of Biomolecular Functional Engineering, College of Engineering, Ibaraki University, 4-12-1 Nakanarusawa-cho, Hitachi 316-8511, Japan. Electronic address: tkitano@mx.ibaraki.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kitano
authors.affiliation: Department of Forensic Medicine, Yamagata University School of Medicine, 2-2-2 Iidanishi, Yamagata 990-9585, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Umetsu
mesh_terms: D000595:Amino Acid Sequence; D000606:Amino Sugars / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D007814:Larva / Q000737:chemistry; D037102:Lectins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D009036:Moths / Q000737:chemistry*; D009113:Muramidase / Q000737:chemistry; D010802:Phylogeny
chemical_list: D000606:Amino Sugars; D037102:Lectins; C079920:Phalera flavescens agglutinin; C000458:N-acetyllactosamine; D009113:Muramidase
keywords: Evolution; Gene; Lectin; Lobster moth; Lysozyme