ABSTRACT
The microbial component of ecosystems represents the first tier of response to sustained systemic disturbance. Indices of microbial diversity and function are also relevant to the assessment of the potential for homeostatic ecosystem recovery. Research approaches based on molecular analysis of microbial diversity and physiology are critical for assessing ecosystem health indices at the fundamental level of structures and functions that are dependent on microorganisms such as bacteria, fungi, and viruses. This study provides two methods developed to analyze protein molecules extracted from natural aquatic microbial communities. The first method yields denatured protein molecules that can be resolved electrophoretically, and the second method yields protein molecules with preserved enzymatic activities. Electrophoretic resolution of proteins leads to the construction of profiles that provide information on population dynamics and ecological succession in response to specific disturbances. Direct analysis of microbial community enzymes provides qualitative and quantitative information on biogeochemical processes which sustain ecosystem health. In order to demonstrate the utility of these methods, aquatic samples collected from a pollution-prone estuarine ecosystem were processed to 208reveal variations in protein profiles and spectra of enzyme activities characteristic of microbial physiological responses to environmental factors.
