Marine sponge-associated bacteria as a potential source for polyhydroxyalkanoates

Abstract

Marine sponges are filter feeding porous animals and usually harbor a remarkable array of microorganisms in their mesohyl tissues as transient and resident endosymbionts. The marine sponge-microbial interactions are highly complex and, in some cases, the relationships are thought to be truly symbiotic or mutualistic rather than temporary associations resulting from sponge filter-feeding activity. The marine sponge-associated bacteria are fascinating source for various biomolecules that are of potential interest to several biotechnological industries. In recent times, a particular attention has been devoted to bacterial biopolymer (polyesters) such as intracellular polyhydroxyalkanoates (PHAs) produced by sponge-associated bacteria. Bacterial PHAs act as an internal reserve for carbon and energy and also are a tremendous alternative for fossil fuel-based polymers mainly due to their eco-friendliness. In addition, PHAs are produced when the microorganisms are under stressful conditions and this biopolymer synthesis might be exhibited as one of the survival mechanisms of sponge-associated or endosymbiotic bacteria which exist in a highly competitive and stressful sponge-mesohyl microenvironment. In this review, we have emphasized the industrial prospects of marine bacteria for the commercial production of PHAs and special importance has been given to marine sponge-associated bacteria as a potential resource for PHAs.

Keywords:

• Marine sponge
• sponge-associated bacteria
• biopolymers
• polyhydroxyalkanoates
• polyhydroxybutyrate

Disclosure statement

The authors declare that they have no conflict of interest. The authors alone are responsible for the content and writing of this article. The first author G. Sathiyanarayanan would like to thank Konkuk University, South Korea for KU Brain pool fellowship. This study was partially supported by National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2015R1A2A2A04006014 and NRF-2015M1A5A1037196), South Korea. GSK is thankful to the Department of Biotechnology (DBT), Govt. of India for a research grant. JS is thankful to Department of Science and Technology (DST).