Open AccessThe role of polyglucose in oxygen‐dependent respiration by a new strain of Desulfovibrio salexigens
Author(s) -
Niel Ed W.J.,
Pedro Gomes Teresa M.,
Willems Anne,
Collins Matthew D.,
Prins Rudolf A.,
Gottschal Jan C.
Publication year - 1996
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.1996.tb00121.x
Subject(s) - oxygen , respiration , biology , anoxic waters , anaerobic exercise , anaerobic respiration , biochemistry , strain (injury) , desulfovibrio , heterotroph , metabolism , catalase , sulfate reducing bacteria , cellular respiration , bacteria , food science , botany , chemistry , ecology , oxidative stress , anatomy , physiology , genetics , organic chemistry
Desulfovibrio salexigens strain Mastl was isolated from the oxic/anoxic interface of a marine sediment. Growth under sulfate‐reducing conditions was accompanied by polyglucose accumulation in the cell with every substrate tested. Highest polyglucose storage was found with glucose (0.8–1.0 g polyglucose (g protein) −1 ), but the growth rate with this substrate was very low (0.015 h −1 ). Anaerobically grown cells of strain Mastl exhibited immediate oxygen‐dependent respiration. The endogenous oxygen reduction rate was proportional to the polyglucose content. The rate of aerobic respiration of pyruvate was also directly related to the polyglucose content indicating that this organism was only able to respire with oxygen as long as polyglucose was present. Maximum oxygen reduction rates were found at air saturating concentrations and were relatively low (3–50 nmol O 2 min −1 (mg protein) −1 ). Catalase was constitutively present in anaerobically grown cells. When batch cultures were exposed to oxygen, growth ceased immediately and polyglucose was oxidized to acetate within 40–50 h. Like the oxygen reduction activity, the nitro blue tetrazolium (NBT)‐reduction activity in these cells was proportional to the polyglucose content. Under anaerobic starvation conditions there was no correlation between the NBT‐reduction activity and polyglucose concentration and polyglucose was degraded slowly within 240 h. The ecological significance of aerobic polyglucose consumption is discussed.