Genetic evidence for bacterial chemolithoautotrophy based on the reductive tricarboxylic acid cycle in groundwater systems.
Geologically and chemically distinct aquifers were screened for the presence of two genes coding for key enzymes of the reverse tricarboxylic acid (rTCA) cycle in autotrophic bacteria, 2-oxoglutarate : ferredoxin oxidoreductase (oorA) and the beta subunit of ATP citrate lyase enzymes (aclB). From 42 samples investigated, aclB genes were detected in two and oorA genes in six samples retrieved from polluted and sulfidic aquifers. aclB genes were represented by a single phylotype of almost identical sequences closely affiliated with chemolithoautotrophic Sulfurimonas species. In contrast, sequences analysis of oorA genes revealed diverse phylotypes mainly related to sequences from cultivation-independent studies.
Institute of Ecology, University of Innsbruck, Technikerstr. 25, 6020 Innsbruck, Austria. albin.alfreider@uibk.ac.at
Albin
A
Alfreider
Carsten
C
Vogt
D001419:Bacteria / Q000235:genetics* / Q000378:metabolism*; D052837:Chemoautotrophic Growth; D002952:Citric Acid Cycle / Q000235:genetics*; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005798:Genes, Bacterial; D060587:Groundwater / Q000382:microbiology*; D053858:Metabolic Networks and Pathways / Q000235:genetics*; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010802:Phylogeny; D017422:Sequence Analysis, DNA
D004269:DNA, Bacterial