A comparison of protein extraction methods optimizing high protein yields from marine algae and cyanobacteria

Abstract

Algae are a diverse group of aquatic autotrophs that represent important models for studying morphology, physiology, and molecular biology. Many, because of their adaptation to the marine environment, cell wall composition, and secondary metabolites, present difficulties when trying to extract significant amounts of protein for analyses. In this study, we compared protein extraction methods for 39 different species of marine algae and cyanobacteria. Since successful protein detection requires the liberation of protein from a cell, the goal of the current investigation was to establish a high yield protein extraction method that would allow for protein extraction from different organisms ranging from cyanobacteria, unicellular, multicellular, and coenocytic algae. Six protein extraction assays were tested (three from literature citations and three from commercially available kits). A modification of the technique originally described by Barbarino and Lourenco (J Appl Phycol 17:447–460, 2005) displayed significantly higher yields (p > 0.001, average of 6.7–30.87% dry weight) in all algal and cyanobacterial species examined. Protein yields using this modified procedure were especially successful in the Trebouxiophyceae, Bangiophyceae, Phaeophyceae, and Cyanobacteria.