This project funded the acquisition of high-resolution mass spectrometry instrumentation to enable the study of proteins and other organic materials produced by marine microbes. In recent years there have been great improvements in the mass accuracy, scanning speed, and multiplexing capabilities of mass spectrometers. As a result, the new generation of instruments are capable of interrogating the profound molecular complexity of marine microbial ecosystems and can provide new insights into biogeochemical cycling and ecosystem function. In the study of laboratory model organisms, proteomics techniques have been shown to be nearly equivalent to the sequencing depth of transcriptional studies using this latest generation of instrumentation. Hence, applying these advances in analytical capability should be particularly useful in their application to marine environments, where there is even greater complexity - for example in interrogating the metaproteomic depth of mixtures of numerous different microbial populations. These advances in instrumentation will also be of great benefit in the study of the roles of metals within organic material through the detection of the unique metal isotopic distributions within small molecules and proteins.