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Biogeography of Marine Bacteria Francisco Rodríguez-Valera Universidad Miguel Hernandez Alicante, Spain Biogeography is the study of the geographical distribution of species Cosmopolitan-widespread geagraphic distribution Endemic-only found at certain geographical areas Baas-Becking (1934)
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Biogeography of Marine Bacteria Francisco Rodríguez-Valera Universidad Miguel Hernandez Alicante, Spain
Biogeography is the study of the geographical distribution of species • Cosmopolitan-widespread geagraphic distribution • Endemic-only found at certain geographical areas
Baas-Becking (1934) • Alles is overal maar het milieu selecteert • All is everywhere but the environment select
Prediction • Similar habitats will harbour similar populations regardless of location • Highly relevant for biodiversity studies
Some problems inherent toBaas-Becking axiom • Replacement rate under low selective pressure • Identity of habitat
Problems specific to the study of bacterial biogiography • Sampling • (how many species of bacteria there are?) • Definition of bacterial species • Establishing identity and degree of relatedness
Culturability of bacteria from natural environments • Planktonic marine bacteria • 1 in 103 to 105 • 50% metabolically active • Soil bacteria • 1 in 200
ITS ITS 1500 bp 3000 bp 120 bp Spacer Region Primer 2 Primer 1
~ 420 pb ITS 16S ~ 650 pb 23S ~ 75 pb tRNA-Ile tRNA-Ala ESQUEMA DEL AMPLICÓN DE RISA DE SAR11 Zonas hipervariables