FINE STRUCTURE OF CAPITULAR FILAMENTS IN THE COENOCYTIC GREEN ALGAPENICILLUS¹,²,³

Abstract

SUMMARY Capitular filaments of Penicillus capitatus contain a large central vacuole. The parietal cytoplasm is densely packed, devoid of chloroplasts in the growing tip, and becomes convoluted and sponge‐like as extensions of the vacuole penetrate the cytoplasm in mature portions of the filament. Structure of organelles and their distribution in the filament are described. The vacuole contains a variety of inclusions, such as membranous configurations, spherical bodies, electron dense bodies, and calcium oxalate monohydrate crystals, each of the latter surrounded by a chamber associated with microtubules. Endophytic bacteria are present throughout the vacuole and occasionally in the tip cytoplasm. Some vacuolar components of P. pyriformis are described for comparison.

The symbiotic chloroplasts in the sacoglossanElysia clarkiare from several algal species

“…2). In this algal species, starch was deposited in amyloplasts outside the plastid (Turner & Friedmann 1974).…”

Virus–like particles and endophytic bacteria in Paraphysomonas and Chromophysomonas (Chrysophyceae)

“…Bacteria: Endophytic bacteria have so far been reported from several algae, including the Chlorophyceae (Kochert & Olson 1970, Burr & West 1970, Turner & Friedmann 1974, Lee & Kochert 1976, Dawes & Lohr 1978, Mariani Colombo 1978, Euglenophyceae (Leedale 1969, Peterfi et al 1979, Kies 1980, Chrysophyceae (Belcher 1969, Hibberd 1971, Wujek 1978, Xanthophyceae (Ott 1979), Raphidophyceae (Heywood 1978) and Dinophyceae (Dodge 1973, Silva 1978, Lucas 1982. With the exception of the intranuclear bacteria described from some Euglenophyceae (Leedale 1969) and Dinophyceae (Silva 1978) all algae contained the bacteria free in the cytoplasm or enclosed in vesicles in the cytoplasm.…”

Chemical interactions between marine macroalgae and bacteria

“…For example, many coenocytic green macroalgae such as Caulerpa, Codium, Bryopsis and Penicillus spp. have been shown to harbour endosymbiotic bacteria, as shown by microscopic studies (Burr & West 1970, Turner & Friedmann 1974, Dawes & Lohr 1978, Rosenberg & Paerl 1981. However, only in Caulerpa taxifolia could it be shown, using molecular approaches, that Herbaspirillum sp.-related bacteria are host-specific endosymbionts (Meusnier et al 2001, Delbridge et al 2004.…”