Antagonistic interactions between filamentous heterotrophs and the cyanobacterium Nostoc muscorumReportar como inadecuado

Antagonistic interactions between filamentous heterotrophs and the cyanobacterium Nostoc muscorum - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

BMC Research Notes

, 4:357

First Online: 13 September 2011Received: 06 May 2011Accepted: 13 September 2011DOI: 10.1186-1756-0500-4-357

Cite this article as: Svercel, M., Saladin, B., van Moorsel, S.J. et al. BMC Res Notes 2011 4: 357. doi:10.1186-1756-0500-4-357


BackgroundLittle is known about interactions between filamentous heterotrophs and filamentous cyanobacteria. Here, interactions between the filamentous heterotrophic bacteria Fibrella aestuarina strain BUZ 2 and Fibrisoma limi BUZ 3 with an axenic strain of the autotrophic filamentous cyanobacterium Nostoc muscorum SAG 25.82 were studied in mixed cultures under nutrient rich carbon source present in medium and poor carbon source absent in medium conditions.

FindingsF. aestuarina BUZ 2 significantly reduced the cyanobacterial population whereas F. limi BUZ 3 did not. Physical contact between heterotrophs and autotroph was observed and the cyanobacterial cells showed some level of damage and lysis. Therefore, either contact lysis or entrapment with production of extracellular compounds in close vicinity of host cells could be considered as potential modes of action.

The supernatants from pure heterotrophic cultures did not have an effect on Nostoc cultures. However, supernatant from mixed cultures of BUZ 2 and Nostoc had a negative effect on cyanobacterial growth, indicating that the lytic compounds were only produced in the presence of Nostoc.

The growth and survival of tested heterotrophs was enhanced by the presence of Nostoc or its metabolites, suggesting that the heterotrophs could utilize the autotrophs and its products as a nutrient source. However, the autotroph could withstand and out-compete the heterotrophs under nutrient poor conditions.

ConclusionsOur results suggest that the nutrients in cultivation media, which boost or reduce the number of heterotrophs, were the important factor influencing the outcome of the interplay between filamentous heterotrophs and autotrophs. For better understanding of these interactions, additional research is needed. In particular, it is necessary to elucidate the mode of action for lysis by heterotrophs, and the possible defense mechanisms of the autotrophs.

Electronic supplementary materialThe online version of this article doi:10.1186-1756-0500-4-357 contains supplementary material, which is available to authorized users.

Download fulltext PDF

Autor: Miroslav Svercel - Bianca Saladin - Sofia J van Moorsel - Sarah Wolf - Homayoun C Bagheri


Documentos relacionados