N-159. Crenarchaeal Prevalence in the Elfin Forest at El Yunque Rain Forest in Puerto Rico

I. Santiago-Rivera, C. E. Bonilla-Rivera, J. R. Perez-Jimenez;
Univ. del Turabo, Gurabo, PR.

Crenarchaeota are not longer restricted to thermally extreme conditions. They have been documented in mesophilic environments, such as boreal forest and tropical hypersaline mats. We aim to disclose the crenarchaeal prevalence, distribution and endemicity within the Elfin Forest at El Yunque Rain Forest (Puerto Rico, USA). Genomic DNA were extracted from soil samples collected at various seasons, depths and plots. A specific portion of the 16S rDNA was amplified for Terminal Restriction Fragment Length Polymorphism (16S rDNA-TRFLP) digested of with HhaI. A total of 732 TRFs (representing 190 different sizes) were obtained on a set of 12 samples. Minor peaks dominated the profiles TRFs per sample ranged from 18 to 79. Three TRFs were found in all samples (81-, 113-, and 133-bp). 54 TRFs appeared once. 66.3% of the TRFs appeared in 4 samples or less. Studied plots showed to be diverse within and across them. Diversity increases for June rather than December. Heterogeneity is higher at top soli (0-5 cm), but prevalence of shared peaks was greater at deeper soils (5-10 cm). Opposite trends were preliminarily observed for Archaeal diversity prevalence. Characterization of clonal library for native crenarchaeal is in progress. Diverse crenarchaeal assemblage is evident in the Elfin Forest. We hypothesize that crenarchaeota, on deep soil, seems to be responsible of replenishing the nitrate pool for anaerobic metabolisms by means of ammonia oxidation.