抄録
Needle-like filamentous bacteria have been isolated commonly from the cultures of three marine microalgae including Chattonella marina, Heterosigma akashiwo and Tetraselmis sp. All filamentous strains showed good growth in the peptone-yeast extract medium with artificial sea water, but failed to grow in the medium with 3% NaCl. A major group of filamentous bacteria showed neither flagellar nor gliding motilities and formed whitish pink and slightly rough colonies on the agar medium. A major pigment extracted from cells of the whitsh pink-colored filamentous strains (WP strains) was considered to be flexixanthin-like carotenoid according to its absorption spectrum. All of WP strains and one greenish orange (OG) strain among filamentous isolates had mole% of GC contents of DNA from 58.7 to 60.0%. DNA probes prepared from the representative strains of WP filamentous bacteria were hybridized with DNAs from all of WP strains and the OG strain but not with those from other filamentous strains and Cytophaga-Flexibacter reference strains.
