Effect of Conventional and Alternative Fuels on a Marine Bacterial Community and the Significance to Bioremediation

Abstract

Understanding the effect of conventional and alternative fuels on the marine bacterial community is crucial, as it pertains to the impact, biodegradation, and final fate of these fuels in the environment. Metagenomics analysis demonstrated that conventional and alternative fuels promoted the growth of Proteobacteria. Marinobacter and Desulfovibrio were predominant in seawater exposed to conventional jet propellant-5 (JP-5), while Hyphomonas and Rhodovulum were most abundant in seawater with hydroprocessed renewable jet fuel (HRJ) and conventional F-76 diesel, respectively. The phyla Bacteroidetes, Firmicutes, and Lentisphaerae were underrepresented in samples with fuel, and these phyla were largely comprised of unclassified bacteria. Culture-dependent tests isolated several of the same genera detected in high abundance by metagenomics DNA sequencing, including Marinobacter, Rhodovulum, and Halobacillus. Growth studies in fuel and gas chromatography analysis demonstrated that isolates grew in fuel and metabolized hydrocarbons efficiently. The hydrocarbon degradation profile of each bacterium was conserved from conventional to alternative fuels. The study indicated that bacteria must out-compete others to get established and proliferate. Competition between hydrocarbon degraders was an important factor affecting the bioremediation process. This study provides insights into the growth characteristics of hydrocarbon-degrading bacteria and the effects of fuel on marine bacterial communities.

Transcriptomic Analyses Elucidate Adaptive Differences of Closely Related Strains of Pseudomonas aeruginosa in Fuel

“…Competition between closely related hydrocarbon degraders is an important factor affecting the bioremediation process (41). This study provides new insight into the mechanistic differences between closely related strains in relation to adaptation and survival in a hydrocarbon-rich environment.…”

Draft Genome Sequence of Achromobacter spanius Strain 6, a Soil Bacterium Isolated from a Hydrocarbon-Degrading Microcosm

“…The NCBI Prokaryotic Genome Annotation Pipeline predicted multiple genes responsible for aromatic degradation, including naphthalene 1,2-dioxygenase, gentisate 1,2-dioxygenase, catechol 1,2-dioxygenase, and protocatechuate 3,4-dioxygenase. Understanding microbial interactions and bacterial community structure in environments contaminated with hydrocarbons is essential when developing bioremediation strategies ( 10 ). The genome sequence of A. spanius strain 6 will help us understand the genetic mechanisms utilized by this organism to thrive in hydrocarbon-rich environments.…”

Draft Genome Sequence of Byssochlamys sp. Isolate BYSS01, a Filamentous Fungus Adapted to the Fuel Environment

“…Using the Carbohydrate-Active Enzymes (CAZy) database ( 10 ), a total of 334 fungal enzymes involved in carbohydrate metabolism and assimilation were identified (E value, 1 × 10 −4 ), including glycoside hydrolases ( n = 113), carbohydrate esterases ( n = 77), glycosyl transferases ( n = 76), enzymes involved in auxiliary activities ( n = 46), carbohydrate-binding modules ( n = 21), and polysaccharide lyases ( n = 1). The Transporter Classification Database (TCDB; http://www.tcdb.org/ ) identified 283 major facilitator superfamily (MSF) transporters with an E value of 1 × 10 −5 , reflecting the ability of the BYSS01 isolate to extrude toxic compounds; efflux pumps have been shown to aid in adaptation to hydrocarbons in bacteria ( 11 , 12 ).…”