Accompanying data

Phototrophic Purple Sulfur Bacteria as Heat Engines in the South Andros Black Hole

Rodney A Herbert1,*, Andrew Gall2, Takashi Maoka3,Richard J. Cogdell4,Bruno Robert2, Shinichi Takaichi5, Stephanie Schwabe6

1 University of Dundee,School of Life Sciences, Division of Environmental and Applied Biology, DundeeDD1 4HN, United Kingdom. 2 Commissariat à l'Energie Atomique, Institut de Biologie et Technologies de Saclay, Gif sur Yvette F-91191, France. 3 Research Institute for Production Development, Shinogamo-morimoto-cho, Sakyou-ku, Kyoto 606-0805, Japan. 4 University of Glasgow, Institute of Biomedical and Life Sciences, Biomedical research building, GlasgowG12 8TA, United Kingdom. 5Nippon Medical School, Biological Laboratory, Nakahara, Kawasaki 211-0063, Japan.6 International Blue Holes Foundation, 5 Longitude Lane, Charleston, SC29401, United States of America.* Author for correspondence (e-mail andrew.gall@cea.f;; Tel:+44 (0)1382 344767(R.A.H);Fax: +44 (0)1382 344275(R.A.H)).

Time-line of the dive video.

TCR 10:38:10:10 / Arriving from the air. When compared with the surrounding water bodies (top of screen) the colour of the water appears black
TCR 10:42:23:06 / The dive team enters the water. The water is crystal clear and blue in colour. The divers follow a shot line that descends into the lake.
TCR 10:42:50:00 / The diver with the red helmet stops. The water is still clear and blue. This is followed by footage of the shot line disappearing into a “solid” layer in the water.
TCR 10:43:05:24 / The diver with the red helmet stops, looks down, and shakes his head. The shot line disappears.
TCR 10:43:28:12 / The diver with the blue helmet follows the shot line and disappears into the layer. The layer is so viscous that his lower body has totally disappeared from view before his waist enters the bacterial layer.
The outline of this diver can still be observed long after he has gone out of camera shot and is due to the extreme viscosity of the bacterial plate.
The diver with the yellow helmet follows him.
TCR 10:43:44:20 / The scene goes black as the divers descend through the bacterial layer. A purple haze is observed, illuminated by the divers lights.
TCR 10:43:55:06 / The divers exit under the purple layer, the water is crystal clear again but the only illumination comes from the flash lights.
TCR 10:44:36:24 / The divers reach the bottom that is pitch black. There is no phototrophic growth.
TCR 10:46:23:13 / The divers begin their ascent from the bottom and again pass through the purple layer.
TCR 10:46:38:20 / When the diver exits the bacterial layer he does not cause any disturbance of the mat. This is due to the viscosity of the 1m thick layer of phototrophic bacteria.
TCR 10:46:51:07 / Close-up of the diver with the yellow helmet as he leaves the microbial layer. The surrounding water is crystal clear as he looks upwards.
TCR 10:46:58:12 / The divers reach the surface. The silver ring on the diver has been blackened by sulfide present in the lower water mass.