EXTREMOPHILES as Astrobiological Models. Группа авторов

Analyte (mg L-1) H1NS°C2 SW1NS°C SW4FeV3 Na 3.454 3.457 3.453 Ca 2.285 2.119 2.870 Al 1.024 1.258 2.006 Fe (total) 0.975 0.974 0.997 Si 18.579 21.932 25.706 B 0.697 0.723 0.760 K 2.864 3.965 3.401 Mg 0.119 0.138 0.945 Zn 0.0147 0.00455 0.0362 Mn 0.00604 0.00618 0.0256 Mo 0.00 0.00 0.00 Se 0.0289 0.0242 0.0251 Ni 0.00 0.00 0.00 Pb 0.00 0.00 0.00 Cr 0.00 0.00 0.00 Cd 0.00164 0.00178 0.00236 Cu 0.00 0.00 0.00 Hg 0.00 0.00 0.00 As (total) 0.0242 0.0201 0.0209 S 0.0312 5.143 17.833 Sr 0.0832 0.00596 0.0187 NO₂/NO₃, N-NO₃ (µM) 0.00 0.00 3.453 NH₄,N-NH₄ (µM) 19.550 79.023 5.780 PO₄,P-PO₄ (µM) 0.00 27.372 0.00 SO4 (µM) 0.00 0.00 222.0 Conductivity (µScm^-1) 13.9 167.2 516

¹ Analysis by inductively coupled plasma optical emission spectrometry and wet chemistry.

      ² Column 1 Data from Bizzoco and Kelley [1.3].

      ³ Column 3 data from Bizzoco and Kelley [1.2].

      H1NS°C, Hawai’i 1 nonsulfur cave, SW1NS°C Sulphur Works 1 nonsulfur cave, SW4FeV, Sulphur Works 4 iron vent.

The Hawai’i H1 sample (Figure 1.3a) was collected from a hard lava cave ceiling (Figure 1.2a) and contained strong peaks for aluminum (Al), silicon (Si) and iron (Fe). The aluminum peak was also formed by a smaller peak of iridium (Ir). Although characterized as a nonsulfur cave, a small sulfur (S) peak was present in the collected sample and was a characteristic of this cave site. Also observed was a strong peak for oxygen (O) and moderate peaks for titanium (Ti) and several biologically important elements, potassium (K), sodium (Na), magnesium (Mg) and calcium (Ca); each of these peak identities was further documented by analyzing several spectra (data not shown). Titanium has been found along with silicon coated on rock surfaces in the Ka’u desert on the Big Island [1.6] and in most Hawai’i steam cave/vent samples, but titanium has no known role in metabolism. The Lassen nonsulfur cave site SW1 was a shallow cave (Figure 1.2b) composed of soft backing material and the immediate sampling was guided by visual access. There was a distinctive red gelatinous material in the collected sample that proved to be noncellular upon microscopic examination. The nonsulfur SW1 spectrum (Figure 1.3b) had far fewer peaks than the Hawaiian H1 counterpart and contained as its main peaks silicon (Si) and oxygen (O) with smaller peaks for titanium (Ti) and carbon (C). Lassen iron vent SW4 was sampled as a thin (~2–3 mm) soft iron (III) oxide deposit collected from a hard rounded rock surface within the vent (Figure 1.2e, f). The spectrum (Figure 1.3c) contained strong peaks for iron (Fe), silicon (Si), oxygen (O) and aluminum (Al) with a moderate sulfur (S) peak and a smaller carbon (C) peak.

      1.3.3 Steam and Steam Deposit Collection: Control Methods

       Steam Controls

      To control for the presence of foreign DNA in our sample analysis of DNA from steam-condensed samples, we used Millipore filtered (0.22 µm membrane) autoclaved Barnstead purified water. The water was converted to steam next to a cave or vent sampled and collected in identical fashion to steam samples from fumaroles. After collection, samples were analyzed with cave or vent samples by (1) PCR, (2) filtration of 10–15 mL samples on 13 mm black