Biosurfactants are a class of functional molecules produced and secreted by microorganisms, which play important roles in cell physiology such as flagellum-dependent or -independent bacterial spreading, cell signaling, and biofilm formation. They are amphipathic compounds and comprise a variety of chemical structures, including rhamnolipids, typically produced by Pseudomonas spp. and also reported within other bacterial genera. The present study is focused on Burkholderia kururiensis KP23(T), a trichloroethylene (TCE)-degrading, N-fixing, and plant growth-promoting bacterium. Herein, we describe the production of rhamnolipids by B. kururiensis, and its characterization by LTQ-Orbitrap Hybrid Mass Spectrometry, a powerful tool that allowed efficient identification of molecular subpopulations, due to its high selectivity, mass accuracy, and resolving power. The population of rhamnolipids produced by B. kururiensis revealed molecular species commonly observed in Pseudomonas spp. and/or Burkholderia spp. In addition, this strain was used as a platform for expression of two Pseudomonas aeruginosa biosynthetic enzymes: RhlA, which directly utilizes β-hydroxydecanoyl-ACP intermediates in fatty acid synthesis to generate the HAA, and RhlB, the rhamnosyltransferase 1, which catalyzes the transfer of dTDP-L-rhamnose to β-hydroxy fatty acids in the biosynthesis of rhamnolipids. We show that rhamnolipid production by the engineered B. kururiensis was increased over 600 % when compared to the wild type. Structural analyses demonstrated a molecular population composed mainly of monorhamnolipids, as opposed to wild-type B. kururiensis and P. aeruginosa in which dirhamnolipids are predominant. We conclude that B. kururiensis is a promising biosurfactant-producing organism, with great potential for environmental and biotechnological applications due to its non-pathogenic characteristics and efficiency as a platform for metabolic engineering and production of tailor-made biosurfactants.

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The electricity demand of offshore oil and gas platforms are traditionally supplied by gas turbines operating with natural gas extracted from the field or fossil fuels emitting CO2 and NOx. Offshore wind power is an interesting alternative to supply such a demand as it can be produced close to the oil and gas field and providing clean and renewable electricity. The objective of this research is to investigate, as a preliminary approach, the techno-economic viability of supplying electricity demand of an oil and gas field by a floating offshore wind farm. An oil and gas field locates in the southeast of the State of Rio de Janeiro, Brazil, with a distance of about 130 km from the shoreline, is selected as a case study. The wind resource at the local is obtained using in-situ measured data. Four wind turbines are studied and compared through their capacity factor and energy production. Afterward, four wind farms composing of the selected turbines are proposed based on the available wind energy and the field demand. The cost of energy produced by the wind farm is calculated, and the results are compared to the conventional method of the electricity supply.

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