Study on two methylotrophic and halophilic methanogens, Methanosarcina siciliae HI350 and Methanolobus taylorii GS-16

Miscellaneous · Sat Jan 01 00:00:00 EST 1994

OSTI ID:7026799

Ni, S

Strain HI350, similar to Methanolobus siciliae T4/M[sup T] (T = type strain) morphologically and physiologically, was isolated from an oil well in the Gulf of Mexico. Catabolic substrates included methanol, trimethylamine, dimethyl sulfide, and methane thiol, but not H[sub 2]-CO[sub 2], formate, or acetate. Growth was fastest in the presence of 0.4 to 0.6 M Na[sup +], in the presence of 60 to 200 mM Mg[sup 2+], at pH 6.5 to 6.8, and at 40[degrees]C. Methanolobus siciliae T4/M[sup T] was closely related to Methanosarcina. Transfer of Methanolobus siciliae T4/M[sup T] to the genus Methanosarcina as Methanosarcina siciliae is proposed with strain HI350 as its reference strain. Degradation of dimethyl sulfide or methane thiol by strain HI350 was complete, and stoichiometric quantities of methane and hydrogen sulfide were formed. Studies of cell-free extracts suggested that enzymes for degradation of dimethyl sulfide and methane thiol were inducible, whereas those for the degradation of methanol or trimethylamine were constitutive. Methanolobus taylorii GS-16, a moderately halophilic and alkcaliphilic methanogen, grows over a wide pH range. The key observation indicative of the involvement of K[sup +] transport in cytosolic acidification was that valinomycin (0.8 [mu]M), a K[sup +] uniporter, inhibited the growth of strain GS-16 only at alkaline pH. Experiments with resting cells indicated that, at alkaline pH, valinomycin uncoupled catabolic reactions from ATP synthesis. Thus, a K[sup +]/H[sup +] antiporter was proposed to account for the K[sup +] extrusion and the uncoupling effect of valinomycin at alkaline pH.

• Research Organization: Oregon Graduate Inst. of Science and Technology, Beaverton, OR (United States)
• OSTI ID: 7026799
• Resource Relation: Other Information: Thesis (Ph.D.)
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
DIMETHYL SULFIDE
BIODEGRADATION
GULF OF MEXICO
OIL WELLS
METHANOGENIC BACTERIA
GROWTH
METHANOL
METHANOTROPHIC BACTERIA
METHANE
OIL FIELDS
ALCOHOLS
ALKANES
ATLANTIC OCEAN
BACTERIA
CARIBBEAN SEA
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
GEOLOGIC DEPOSITS
HYDROCARBONS
HYDROXY COMPOUNDS
MICROORGANISMS
MINERAL RESOURCES
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PETROLEUM DEPOSITS
RESOURCES
SEAS
SULFIDES
SULFUR COMPOUNDS
SURFACE WATERS
WELLS
560300* - Chemicals Metabolism & Toxicology