title: Characterization of the chemical diversity of glycosylated mycosporine-like amino acids in the terrestrial cyanobacterium Nostoc commune.
abstract: Mycosporine-like amino acids (MAAs) are UV-absorbing pigments, and structurally unique glycosylated MAAs are found in the terrestrial cyanobacterium Nostoc commune. In this study, we examined two genotypes of N.commune colonies with different water extract UV-absorption spectra. We found structurally distinct MAAs in each genotype. The water extract from genotype A showed a UV-absorbing spectrum with an absorption maximum at 335nm. The extract contained the following compounds: 7-O-(β-arabinopyranosyl)-porphyra-334 (478Da), pentose-bound shinorine (464Da), hexose-bound porphyra-334 (508Da) and porphyra-334 (346Da). The water extract from genotype B showed a characteristic UV-absorbing spectrum with double absorption maxima at 312 and 340nm. The extract contained hybrid MAAs (1050Da and 880Da) with two distinct chromophores of 3-aminocyclohexen-1-one and 1,3-diaminocyclohexen linked to 2-O-(β-xylopyranosyl)-β-galactopyranoside. A novel 273-Da MAA with an absorption maximum at 310nm was also identified in genotype B. The MAA consisted of a 3-aminocyclohexen-1-one linked to a γ-aminobutyric acid chain. These MAAs had potent radical scavenging activities in vitro and the results confirmed that the MAAs have multiple roles as a UV protectant and an antioxidant relevant to anhydrobiosis in N. commune. The two genotypes of N. commune exclusively produced their own characteristic glycosylated MAAs, which supports that MAA composition could be a chemotaxonomic marker for the classification of N. commune.
authors.affiliation: Division of Life Science, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Nazifi
authors.affiliation: School of Natural System, College of Science and Engineering, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Wada
authors.affiliation: Division of Functional Genomics, Advanced Science Research Center, Kanazawa University, Takara, Kanazawa 920-0934, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Asano
authors.affiliation: Division of Functional Genomics, Advanced Science Research Center, Kanazawa University, Takara, Kanazawa 920-0934, Japan.
authors.forename: Takumi
authors.initials: T
authors.lastname: Nishiuchi
authors.affiliation: Forensic Science Laboratory, Ishikawa Prefectural Police Headquarters, 1-1 Kuratsuiki, Kanazawa 920-8553, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Iwamuro
authors.affiliation: Forensic Science Laboratory, Ishikawa Prefectural Police Headquarters, 1-1 Kuratsuiki, Kanazawa 920-8553, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Chinaka
authors.affiliation: School of Natural System, College of Science and Engineering, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan.
authors.forename: Seiichi
authors.initials: S
authors.lastname: Matsugo
authors.affiliation: Division of Life Science, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan; School of Natural System, College of Science and Engineering, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan. Electronic address: tsakamot@staff.kanazawa-u.ac.jp.
authors.forename: Toshio
authors.initials: T
authors.lastname: Sakamoto
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D002734:Chlorophyll / Q000032:analysis; D000077194:Chlorophyll A; D002851:Chromatography, High Pressure Liquid; D003511:Cyclohexanols / Q000032:analysis* / Q000302:isolation & purification / Q000378:metabolism; D003512:Cyclohexanones / Q000032:analysis; D019075:Electrophoresis, Capillary; D005838:Genotype; D005998:Glycine / Q000031:analogs & derivatives / Q000032:analysis; D006031:Glycosylation; D008970:Molecular Weight; D050501:Nostoc commune / Q000235:genetics / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000975:Antioxidants; D003511:Cyclohexanols; D003512:Cyclohexanones; D012336:RNA, Ribosomal, 16S; C421025:porphyra-334; D002734:Chlorophyll; D005998:Glycine; D000077194:Chlorophyll A