Distinct ecological niches of marine symbiotic N2 -fixing cyanobacterium Candidatus Atelocyanobacterium thalassa sublineages.

DISTINCT ECOLOGICAL NICHES OF MARINE SYMBIOTIC N 2 -FIXING CYANOBACTERIUM CANDIDATUS ATELOCYANOBACTERIUM THALASSA SUBLINEAGES 1 Kendra A. Turk-Kubo 2 Ocean Sciences Department, University of California, Santa Cruz, CA 95064, USA; Hanna M. Farnelid Ocean Sciences Department, University of California, Santa Cruz, CA 95064, USA; 11 Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, 392 34 Kalmar, Sweden Irina N. Shilova Ocean Sciences Department, University of California, Santa Cruz, CA 95064, USA; Britt Henke Ocean Sciences Department, University of California, Santa Cruz, CA 95064, USA; Jonathan P. Zehr Ocean Sciences Department, University of California, Santa Cruz, CA 95064, USA; 24 1 Date of submission and acceptance 26 2 Corresponding Author: 27 Kendra A. Turk-Kubo 28 Ocean Sciences Department 29 University of California, Santa Cruz 30 1156 High Street 31 Santa Cruz, CA 95064 32 kturk@ucsc.edu 35 Running Title: UCYN-A global diversity 47 Abstract