※一部利用できない機能があります
| 1.
論文 |
論文
|
Nazifi, Ehsan ; Wada, Naoki ; Asano, Tomoya ; Nishiuchi, Takumi ; Iwamuro, Yoshiaki ; Chinaka, Satoshi ; Matsugo, Seiichi ; Sakamoto, Toshio
概要:
Mycosporine-like amino acids (MAAs) are UV-absorbing pigments, and structurally unique glycosylated MAAs are found in th
…
e 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 335 nm. The extract contained the following compounds: 7-O-(β-arabinopyranosyl)-porphyra-334 (478 Da), pentose-bound shinorine (464 Da), hexose-bound porphyra-334 (508 Da) and porphyra-334 (346 Da). The water extract from genotype B showed a characteristic UV-absorbing spectrum with double absorption maxima at 312 and 340 nm. The extract contained hybrid MAAs (1050 Da and 880 Da) 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 310 nm 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.
続きを見る
|
||||
| 2.
論文 |
論文
|
Nazifi, Ehsan ; Wada, Naoki ; Asano, Tomoya ; Nishiuchi, Takumi ; Iwamuro, Yoshiaki ; Chinaka, Satoshi ; Matsugo, Seiichi ; Sakamoto, Toshio
|
