Effect of bacterial satellites on Chlamydomonas reinhardtii growth in an algo-bacterial community

• Published in: Microbiology (New York) 2008-01, Vol.77 (1), p.78-83
• Main Authors: Nikolaev, Yu. A, Plakunov, V. K, Voronina, N. A, Nemtseva, N. V, Plotnikov, A. O, Gogoleva, O. A, Murav'eva, M. E, Ovechkina, G. V
• Format: Article
• Language: English
• Subjects: Biomedical and Life Sciences; Experimental Articles; Life Sciences; Medical Microbiology; Microbiology
• ISSN: 0026-2617; 1608-3237
• DOI: 10.1134/S0026261708010116

The growth characteristics of an algo-bacterial community (Chlamydomonas reinhardtii and bacterial satellites) were studied, as well as the mechanism and patterns of bacterial effect on algae. Four strains of predominant bacteria were isolated and partially characterized. They were assigned to the following taxa: Rhodococcus terrea, Micrococcus roseus, and Bacillus spp. A pure culture of the alga under study was obtained by plating serial dilutions on agarized media. Within the algo-bacterial association, the alga had a higher growth rate (0.76 day⁻¹) and yield (60 μg chlorophyll/ml culture) than in pure cultures (0.4 day⁻¹ and 10 μg chlorophyll/ml culture, respectively). The viability of the algal cells within the association was retained longer than in pure culture. Among the isolated bacterial satellites, strains B1 and Y1, assigned to the species Rhodococcus terrae, had the highest stimulatory effect on algal growth. The culture liquid of bacteria incubated under the conditions not permitting growth stimulated algal growth; the culture liquid of actively growing bacteria had an opposite effect.