Photosynthetic carbon incorporation and turnover in Antarctic cryptoendolithic microbial communities: Are they the slowest-growing communities on earth

Journal Article · Thu Aug 01 00:00:00 EDT 1991 · Applied and Environmental Microbiology; (United States)

OSTI ID:5410002

Johnston, C G; Vestal, J R ^[1]

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1. Univ. of Cincinnati, OH (USA)

The main forms of terrestrial life in the cold, desolate Ross Desert of Antarctica are lichen-dominated or cyanobacterium-dominated cryptoendolithic (hidden in rock) microbial communities. Though microbial community biomass (as measured by extractable lipid phosphate) was well within the range of values determined for their microbial communities, community lipid carbon turnover times (calculated from community lipid biomass, rates of community photosynthetic carbon incorporation into lipids versus temperature, and the in situ temperature record) were among the longest on Earth (ca. 20,000 years). When the temperature is above freezing and moisture is present, moderate rates of photosynthesis can be measured. Lichen communities had a psychrophilic temperature response (maximal rate of 4.5 ng of C h{sup {minus}1}m{sup {minus}2} at 10C) while cyanobacteria communities had maximal rates at 20 to 30C(3 ng of C h{sup {minus}1} m{sup {minus}2}). These extraordinarily slowly growing communities were not nutrient limited. No significant changes in photosynthetic metabolism simple, tenacious microbial communities demonstrate strategies of survival under conditions normally considered too extreme for life.

• OSTI ID: 5410002
• Journal Information: Applied and Environmental Microbiology; (United States), Vol. 57:8; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ANTARCTICA
GEOBOTANY
CYANOBACTERIA
METABOLISM
LICHENS
BIOLOGICAL ADAPTATION
BIOMASS
NUTRIENTS
PHOTOSYNTHESIS
TEMPERATURE EFFECTS
ALGAE
ANTARCTIC REGIONS
BIOLOGY
BOTANY
CHEMICAL REACTIONS
ENERGY SOURCES
EUMYCOTA
FUNGI
MICROORGANISMS
PHOTOCHEMICAL REACTIONS
PLANTS
POLAR REGIONS
RENEWABLE ENERGY SOURCES
SYNTHESIS
550500* - Metabolism