Naslov
Bacterial fatty acids as bio-indicators of microbial processes in the northern Adriatic mucilaginous agregates

Autori
Blažina, Maria ; Najdek, Mirjana ; Fuks, Dragica ; Šilović, Tina ; Ivančić, Ingrid ; Smodlaka, Nenad

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
SAME11-2009 Abstract book / Turk, Valentina & Turk, Samo - Piran, 2009, 56-56

ISBN
978-961-92543-1-8

Skup
11th Symposium on Aquatic Microbial Ecology

Mjesto i datum
Piran, Slovenija, 30.08.2009. - 04.09.2009

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
fatty acids; bacteria; mucilaginous aggregates; northern Adriatic

Sažetak
Throughout the past two decades changes in hydrological regime of northern Adriatic are accompanied by increased frequency of mucilage events. The appearance and distribution of freshly formed aggregates dominated by epipelic diatom Cylindrotheca closterium pointed to intrusions of the oligotrophic high-salinity water from middle Adriatic and formation of saline water traps as an imperative of this phenomenon. A tool based on microbial fatty acids as bioindicators was developed in order to characterize and differentiate aggregates, water masses, and bacterial processes related to organic matter transformation. We compared differences in chemotaxonomic structure and physiological state of the cultured bacterial communities from freshly-formed aggregates, their surrounding waters, oligotrophic high salinity waters and that accompanying mesocosm diatom bloom to provide an insight into the physiological adaptations taking place during the early phase of aggregate formations. Differences in population dominance of the free-living community and its attached counterpart are established in respect to eutrophic, oligotrophic and oligotrophic nutrient-selected trophic state. Very close similarity between the bacterial communities attached to freshly-formed aggregates, the particulate fraction of oligotrophic waters of higher salinity and those ordinarily responding to enclosure in any mesocosm experiment, is observed. In contrast, bacterial community structures and physiological state of the aggregates’ surrounding waters is regularly different from those attached to aggregates, but significantly similar to particulate fraction of northern Adriatic salinity gradient waters. These results suggest a) the same origin of both: the phytoplankton cells and bacterial population belonging to Alteromonadaceae, but also b) the earliest stage of mucilaginous aggregates formation is hastily ceased turbulence of the interleaved elevated salinity water layers into northern Adriatic waters. The complementary metabolisms among Alteromonadaceae and C. closterium enables them both superiority in adaptation to the abruptly changing conditions such as mucilaginous aggregates formation.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA