iConcept Press Logo
Email Password Remember me
Protein Purification: Principles and Trends
Protein Purification: Principles and Trends
iConcept Press

Chapter 10

Protein Purification: Principles and Trends

Proteins from Halophilic Bacteria: Purification and Their Applications

by Beste Çalımlıoğlu and Kazim Yalcin Arga

Viewed: 4800


Halophilic microorganisms and their products are getting more important day by day regarding to their different characteristic features related to extreme conditions. Previous studies on purification of halophilic proteins from both archea and bacteria lead to understand their osmoregulation capacity and the other unique features, as well as main differences between archeal and bacterial halophiles. Generally halophilic bacteria able to survive at the lower range of salinities and have achievability of adaptation to changes in the external salt conditions, comparison with the halophilic archea which requires high salt concentrations to maintain the structural components which causes the need of constant high salt concentration. Because of this reason, the moderately halophilic bacteria has an advantage to be worked at the lower temperatures and the lower salt concentration ranges, i.e. between 3-30 %. In addition, proteins from halophilic bacteria are mentioned as acidic aminoacid abundant which confers to the extensive negatively charged at neutral pH and high aqueous solubility. This negative charge prevents protein aggregation when denatured and leads to highly efficient protein refolding. According to their location as mentioned intracellular, membrane bound or extracellular proteins, salt requirements are also changed. Halophiles are excellent sources of proteins with these all unique properties, especially good sources of enzymes that are not only salt stable but also can resist and carry out reactions under extreme conditions like harsh operational conditions in industrial process.There are different examples and applications for halophilic proteins. For instance, β lactamase from halophilic bacteria used as a potential fusion partner for expression and aggregation-prone heterologous proteins to be expressed in E.coli; extracellular α-amylase production; recombinant productions such as α-amylase from moderate halophile or histidine rich metal binding protein; industrially important enzymes such as lipase, protease and amylase activity were screened and in addition to these enzymes, gelatinase and inulinase activity and DNase, pullulanase and xylanase production were screened; salt sensitive in vitro protein synthesis from extremely halophilic bacteria; determination of salt dependent properties of proteins from extremely halophilic bacteria; nicotinamide adenine dinucleotide-linked malic acid dehydrogenase; extracellular dextrinogenic amylase purification; crystal structure studies carried out such as halophilic dodecin, are some of studies on halophilic bacterial proteins. High salt concentrations and cell requirements cause some problems in purification process and conventional protein purification methods cannot be used easily due to charged molecules, relatively saturated fermentation mediums, molecular bounds. Our aim in this chapter is to describe features, purification methods and applications of proteins such as membrane bound proteins, enzymes or recombinant proteins produced by halophilic bacteria.

Author Details

Beste Çalımlıoğlu
Department of Bioengineering, Faculty of Engineering and Architecture, Istanbul Medeniyet University, Turkey
Kazim Yalcin Arga
Department of Bioengineering, Faculty of Engineering, Marmara University, Turkey


Beste Çalımlıoğlu and Kazim Yalcin Arga. Proteins from Halophilic Bacteria: Purification and Their Applications. In Protein Purification: Principles and Trends. ISBN:978-1-922227-40-9. iConcept Press. 2016.