2010/04/30 by Dirk Schulze‐Makuch, Dirk Schulze-Makuch, Shirin Haque +16 · 1 citation
Biochemistry, Genetics and Molecular Biology · Earth and Planetary Sciences · Environmental Science · Physics and Astronomy · #Methane Hydrates and Related Phenomena #Microbial Community Ecology and Physiology #Paleontology and Stratigraphy of Fossils #physics.bio-ph #q-bio.GN #q-bio.PE
paper · pdf · doi:10.1089/ast.2010.0488
This paper has been withdrawn due to the requirements of the journal it is to be published in that it cannot be posted anywhere else other than in the journal
arxiv created 2010/07/21 · openalex publication_date 2011/04/01 · arxiv updated 2015/05/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Pitch Lake in Trinidad and Tobago is a natural asphalt reservoir nourished by pitch seepage, a form of petroleum that consists of mostly asphaltines, from the surrounding oil-rich region. During upward seepage, pitch mixes with mud and gases under high pressure, and the lighter portion evaporates or is volatilized, which produces a liquid asphalt residue characterized by low water activity, recalcitrant carbon substrates, and noxious chemical compounds. An active microbial community of archaea and bacteria, many of them novel strains (particularly from the new Tar ARC groups), totaling a biomass of up to 10(7) cells per gram, was found to inhabit the liquid hydrocarbon matrix of Pitch Lake. Geochemical and molecular taxonomic approaches revealed diverse, novel, and deeply branching microbial lineages with the potential to mediate anaerobic hydrocarbon degradation processes in different parts of the asphalt column. In addition, we found markers for archaeal methane metabolism and specific gene sequences affiliated with facultative and obligate anaerobic sulfur- and nitrite-oxidizing bacteria. The microbial diversity at Pitch Lake was found to be unique when compared to microbial communities analyzed at other hydrocarbon-rich environments, which included Rancho Le Brea, a natural asphalt environment in California, USA, and an oil well and a mud volcano in Trinidad and Tobago, among other sites. These results open a window into the microbial ecology and biogeochemistry of recalcitrant hydrocarbon matrices and establish the site as a terrestrial analogue for modeling the biotic potential of hydrocarbon lakes such as those found on Saturn's largest moon Titan.