2008 Projects

Title: Structural and functional study of the proteins mediating electron transfer between microorganisms and solid substrates with relevance for bio-energy production

Starting Date: 1/6/2009

Expected Completion Date: 31/5/2011

Principal Investigator:Ricardo O. Louro

Institutions/Research Centers involved: ITQB-UNL, FCT-UNL

Companies involved: EDP Inovação

See the video of PI Ricardo Louro describing the project on the science program Falar Global (in Portuguese)

Abstract:

The demands of energy by society must be met by a portfolio of sources that reduce the current reliance on fossil fuels. It has been argued that microorganisms, and in particular microorganisms growing in unusual habitats can help provide a solution to this problem.

The recent genomic efforts to characterize a wide variety of microorganisms have revealed that some bacteria display a metabolic versatility that may be harnessed for bioengineering purposes. Anaerobic photosynthetic bacteria have been notorious for decades because they can use the excess reducing power provided by sunlight to generate hydrogen. More recently some of these organisms were shown to be able to use metallic compounds such as iron ores in sediments, as a source of electrons to sustain their anaerobic photosynthetic activity. This opens the possibility to develop solar powered microbial fuel cells.

Bacteria belonging to the class of photosynthetic purple alpha-proteobacteria are capable of using iron oxides as electron sources for anaerobic photosynthesis. However, the key proteins in this process have not been characterized, which is a major obstacle to the development of practical applications of these organisms. One of the team members identified the operons in the bacterial species Rhodopseudomonas paluatris and Rhodobacter strain SW2 that are responsible for electron uptake when growing photoautotrophically.