Accumulation of bacterial structural remnants in Antarctic cryptoendolithic (inside of rock) ecosystems, and implications for carbon and nitrogen cycling
Wednesday, October 26, 2005
4:00 - 5:00 pm
LFG 102, UNLV Campus
Abstract
In the Antarctic cryptoendolithic biota, peptidoglycans from bacterial cell walls represent a small amount of matter. However, peptidoglycans are resistant, and can accumulate and persist in the endolithic environment. The presence of a large bacterial necromass has implications for carbon and nitrogen cycles. For example, it causes the microbial community to have a bulk 14C age that is much older than what the living organisms would indicate. Because peptidoglycans are composed of D-amino acids, their accumulation also elevates the overall ratios of D- and L-amino acids in the rock. If time permits, I will report on iron stable isotope data that shed light on the iron cycle in these ecosystems.
Updated September 14, 2005