A breath of fresh air
Article Abstract:
Models of the early atmosphere indicate that the Earth was oxygen-free, containing chemically reduced compounds such as carbon monoxide, hydrogen gas and perhaps methane. The evolution of cyanobacteria was the defining moment in Earth history, with the availability of oxygen change the chemistry of its surface environment forever. Summons and colleagues have described molecular fossils derived from the cell walls of cyanobacteria discovered in 2.5 billion year old sedimentary rocks in Western Australia, providing the earliest direct evidence for cyanobacterial activity.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1999
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Hooded camera
Article Abstract:
Kunjamma, a Brahmin grandmother and clan matriarch, objects to being photographed as a way of capturing her before death. Her family planned to have the portrait taken without her knowledge by having the cameraman set up and then bringing her out to give audience to the neighbors. Her objection to photography is consistent with her objection to indoor plumbing and electric light. The portrait session, which took place in 1936, is the first experience that the family had with photography.
Publication Name: Aperture
Subject: Arts, visual and performing
ISSN: 0003-6420
Year: 1997
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Adenosylcobalamin-dependent methylmalonyl-CoA mutase isozymes in the photosynthetic protozoon Euglena gracilis Z
Article Abstract:
The photosynthetic protozoon Euglena gracilis Z contains adenosylcobalamin-dependent methylmalonyl-CoA mutase (MCM) implicated in propionate metabolism. The specific activity of the Euglena mutase is about 6.5 times greater in propionate-adapted Euglena cells than in photoautotrophic cells. Both enzymes are found in the mitochondria. Findings indicate that propionate-adapted Euglena contains two MCM isozymes. The induced mutase allows photoassimilation of propionate.
Publication Name: Microbiology
Subject: Biological sciences
ISSN: 1350-0872
Year: 1996
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