Project SANTA CLAµS
in the Laboratory for Microbial Oceanography at the University of Hawai'i at Manoa

Accomplishments & Reports: Antarctic Archaeoplankton


Edward DeLong
UC Santa Barbara, Marine Science Institute
Santa Barbara, CA 93106
(delong@marbtech.lscf.ucsb.edu)

and

David M. Karl, Craig L. Moyer
University of Hawaii, SOEST, Department of Oceanography
Honolulu, HI 96822
(dkarl@soest.hawaii.edu)


Archaebacteria are an evolutionarily distinct group of prokaryotes, as genetically distant from "common" eubacteria as they are from eukaryotes. Until very recently, archaebacteria were thought to thrive only in a few disparate niches, consisting of either very hot, very salty, or strictly anaerobic environments. Recent studies show that pelagic marine archaebacteria can constitute a major fraction (>30%) of Antarctic prokaryote biomass in coastal waters off Palmer Station, Antarctica (DeLong et al. 1994). Since surface waters off Palmer Station have yielded the highest biomass estimates of pelagic archaebacteria to date, this area is uniquely suited for studying these unusual microorganisms.

The main objectives of this component of Project SANTA CLAµS were: (1) to confirm the results obtained on a previous LTER expedition regarding the dominance of archaebacteria in the marine plankton near Palmer Station and (2) to describe the larger scale patterns of the "archaeoplankton phenomenon." To accomplish these goals, water samples were collected from a number of diverse locations including open water, coastal and hydrothermal habitats. Samples were also obtained on two separate Drake Passage crossings (at the end of the SANTA CLAµS and at the beginning of the LTER annual cruise in Jan 1995) to examine the relative changes in biomass across the Antarctic Convergence zone (see "Drake Passage Transect" report). Cells were concentrated onto 0.2 µm filters and frozen in a sucrose-based lysis buffer. The frozen samples will be shipped to Santa Barbara for subsequent analysis.


Reference

DeLong, E. F., K. Y. Wu, B. B. Prezelin and R. V. M. Jovine. 1994. High abundance of Archaea in Antarctic marine picoplankton. Nature, 371: 695-697.