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Full-Text Articles in Life Sciences
Ms Analysis Of A Dilution Series Of Bacteria: Phytoplankton To Improve Detection Of Low Abundance Bacterial Peptides, Emma Timmins-Schiffman, Molly P. Mikan, Ying Sonia Ting, H. Rodger Harvey, Brook L. Nunn
Ms Analysis Of A Dilution Series Of Bacteria: Phytoplankton To Improve Detection Of Low Abundance Bacterial Peptides, Emma Timmins-Schiffman, Molly P. Mikan, Ying Sonia Ting, H. Rodger Harvey, Brook L. Nunn
OES Faculty Publications
Assigning links between microbial activity and biogeochemical cycles in the ocean is a primary objective for ecologists and oceanographers. Bacteria represent a small ecosystem component by mass, but act as the nexus for both nutrient transformation and organic matter recycling. There are limited methods to explore the full suite of active bacterial proteins largely responsible for degradation. Mass spectrometry (MS)-based proteomics now has the potential to document bacterial physiology within these complex systems. Global proteome profiling using MS, known as data dependent acquisition (DDA), is limited by the stochastic nature of ion selection, decreasing the detection of low abundance peptides. …
Evaluation Of Electrophoretic Protein Extraction And Database-Driven Protein Identification From Marine Sediments, Eli K. Moore, Brook L. Nunn, Jessica F. Faux, David R. Goodlett, H. Rodger Harvey
Evaluation Of Electrophoretic Protein Extraction And Database-Driven Protein Identification From Marine Sediments, Eli K. Moore, Brook L. Nunn, Jessica F. Faux, David R. Goodlett, H. Rodger Harvey
OES Faculty Publications
Intact proteins comprise a major component of organic carbon and nitrogen produced globally and are likely an important fraction of organic matter in sediments and soils. Extracting the protein component from sediments and soils for mass spectral characterization and identification represents a substantial challenge given the range of products and functionalities present in the complex matrix. Multiple forms of gel electrophoresis were evaluated as a means of enhancing recovery of sedimentary protein before proteomic characterization and compared with a direct enzymatic digestion of proteins in sediments. Resulting tryptic peptides were analyzed using shotgun proteomics and tandem mass spectra were evaluated …
Peptide Hydrolysis And The Uptake Of Dipeptides By Phytoplankton, Margaret R. Mulholland, Cindy Lee
Peptide Hydrolysis And The Uptake Of Dipeptides By Phytoplankton, Margaret R. Mulholland, Cindy Lee
OES Faculty Publications
Rates of peptide hydrolysis (using the fluorescent substrate, lucifer yellow anhydride-labeled tetra-alanine) and dipeptide uptake (using dually labeled, 15N and 13C, dialanine) were measured in phytoplankton cultures and in natural populations during algal blooms dominated by one or two taxa. During most sampling events, both peptide hydrolysis and dipeptide uptake were greatest in the size fraction containing the dominant phytoplankter, suggesting that phytoplankton contribute substantially to or may even dominate observed extracellular peptide hydrolysis and dipeptide uptake in the environment. These are the first data suggesting that dipeptides may be taken up directly by phytoplankton and this may …