title: Lava cave microbial communities within mats and secondary mineral deposits: implications for life detection on other planets.
abstract: Lava caves contain a wealth of yellow, white, pink, tan, and gold-colored microbial mats; but in addition to these clearly biological mats, there are many secondary mineral deposits that are nonbiological in appearance. Secondary mineral deposits examined include an amorphous copper-silicate deposit (Hawai'i) that is blue-green in color and contains reticulated and fuzzy filament morphologies. In the Azores, lava tubes contain iron-oxide formations, a soft ooze-like coating, and pink hexagons on basaltic glass, while gold-colored deposits are found in lava caves in New Mexico and Hawai'i. A combination of scanning electron microscopy (SEM) and molecular techniques was used to analyze these communities. Molecular analyses of the microbial mats and secondary mineral deposits revealed a community that contains 14 phyla of bacteria across three locations: the Azores, New Mexico, and Hawai'i. Similarities exist between bacterial phyla found in microbial mats and secondary minerals, but marked differences also occur, such as the lack of Actinobacteria in two-thirds of the secondary mineral deposits. The discovery that such deposits contain abundant life can help guide our detection of life on extraterrestrial bodies.
authors: Biology Department, University of New Mexico, Albuquerque, New Mexico 87131, USA. dnorthup@unm.edu
authors: D E
authors: DE
authors: Northup
authors: L A
authors: LA
authors: Melim
authors: M N
authors: MN
authors: Spilde
authors: J J M
authors: JJ
authors: Hathaway
authors: M G
authors: MG
authors: Garcia
authors: M
authors: M
authors: Moya
authors: F D
authors: FD
authors: Stone
authors: P J
authors: PJ
authors: Boston
authors: M L N E
authors: ML
authors: Dapkevicius
authors: C
authors: C
authors: Riquelme
mesh_terms: D039903:Actinobacteria / Q000235:genetics; D059552:Caves / Q000737:chemistry* / Q000382:microbiology*; D017753:Ecosystem; D019015:Geologic Sediments / Q000032:analysis / Q000382:microbiology*; D008855:Microscopy, Electron, Scanning; D008903:Minerals / Q000032:analysis; D009516:New Mexico; D016083:Planets; D012336:RNA, Ribosomal, 16S / Q000737:chemistry; D017422:Sequence Analysis, DNA
chemical_list: D008903:Minerals; D012336:RNA, Ribosomal, 16S