Open AccessElectron‐transport‐driven sodium extrusion during methanogenesis from formaldehyde and molecular hydrogen by Methanosarcina barkeri
Author(s) -
MÜLLER Volker,
WINNER Christiane,
GOTTSCHALK Gerhard
Publication year - 1988
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1988.tb14478.x
Subject(s) - methanosarcina barkeri , methanogenesis , formaldehyde , methanol , chemistry , sodium , inorganic chemistry , methanosarcina , redox , nuclear chemistry , methane , biochemistry , organic chemistry
Methanogenesis from formaldehyde or formaldehyde + H 2 , as carried out by Methanosarcina barkeri , was strictly dependent on sodium ions whereas methane formation from methanol + H 2 or methanol + formaldehyde was Na + ‐independent. This indicates that the reduction of formaldehyde to the formal redox level of methanol exhibits a Na + requirement. During methanogenesis from formaldehyde, a ΔpNa in the range of ‐62 mV to ‐80 mV was generated by means of a primary, electron‐transport‐driven sodium pump. This could be concluded from the following results obtained on cell suspensions of M. barkeri.1 The addition of proton conductors or inhibitors of the Na + /H + antiporter had no effect on sodium extrusion. 2 During methanogenesis from formaldehyde + H 2 a ΔΨ of ‐60 mV to ‐70 mV was generated even in the presence of proton conductors. 3 ATPase inhibitors, applied in the presence of proton conductors, had no effect on primary sodium extrusion or generation of a ΔΨ. Evidence for a Na + ‐translocating ATPase could not be obtained.