Characterization of novel Acidobacteria exopolysaccharides with potential industrial and ecological applications

Author(s)

Kielak, Anna M. ; Castellane, Tereza C. L. ; Campanharo, Joao C. ; Colnago, Luiz A. ; Costa, Ohana Y. A. ; Corradi da Silva, Maria L. ; van Veen, Johannes A. ; Lemos, Eliana G. M. ; Kuramae, Eiko E.

• Document type: Journal article
• Source: SCIENTIFIC REPORTS; v. 7, JAN 24 2017.
• Web of Science Citations: 8

Abstract

Acidobacteria have been described as one of the most abundant and ubiquitous bacterial phyla in soil. However, factors contributing to this ecological success are not well elucidated mainly due to difficulties in bacterial isolation. Acidobacteria may be able to survive for long periods in soil due to protection provided by secreted extracellular polymeric substances that include exopolysaccharides (EPSs). Here we present the first study to characterize EPSs derived from two strains of Acidobacteria from subdivision 1 belonging to Granulicella sp. EPS are unique heteropolysaccharides containing mannose, glucose, galactose and xylose as major components, and are modified with carboxyl and methoxyl functional groups that we characterized by Fourier transform infrared (FTIR) spectroscopy. Both EPS compounds we identified can efficiently emulsify various oils (sunflower seed, diesel, and liquid paraffin) and hydrocarbons (toluene and hexane). Moreover, the emulsions are more thermostable over time than those of commercialized xanthan. Acidobacterial EPS can now be explored as a source of biopolymers that may be attractive and valuable for industrial applications due to their natural origin, sustainability, biodegradability and low toxicity. (AU)

• FAPESP's process: 10/11957-6 - Construction of mutant gene exoz involved in the synthesis of repeating subunits of EPS and the genes phbA, phbB and phbC responsible for the synthesis of PHB in Rhizobium tropici SEMIA 4080
• Grantee: Eliana Gertrudes de Macedo Lemos
• Support Opportunities: Regular Research Grants