Bakterie metanotroficzne w ekosystemach

POST. MIKROBIOL.,
1999, 38, 4, 295
BAKTERIE METANOTROFICZNE
W EKOSYSTEMACH
Agnieszka Rożej, Witold Stępniewski, Wanda Małek
1. Wstęp. 2. Systematyka metanotrofów. 3. Wpływ czynników fizycznych i chemicznych na
utlenianie metanu. 4. Metody identyfikacji bakterii metanotroficznych. 5. Występowanie bakterii
utleniających metan w naturalnych środowiskach. 6. Aktywność bakterii metanotroficznych w
różnych środowiskach. 7. Zależności między metanotrofami a innymi grupami bakterii. 8. Wpływ
sposobu użytkowania gleby na utlenianie metanu. 9. Nowe kierunki badań bakterii
metanotroficznych. 10. Podsumowanie
Methanotrophic bacteria in ecosystems
Abstract:
Methane is an important greenhouse gas, concentration of which in
atmosphere has dramatically increased during the last 300 years. Biological CH4 oxidation by
methanotrophs plays an important role in reducing methane emission to the atmosphere, and
thus in moderating of methane impact on global Earth climate warming. Methane-oxidizing
microorganisms are widespread bacteria in different habitats, specially in aerobic soils and
sediments and their number is correlated with methane and oxygen concentration.
Methanotrophs are divided into three types: I, II and X on the basis of their physiological,
biochemical and genotypic properties. Type I of these bacteria, with high affinity to CH4,
developes in aerated soils with low levels of methane, whereas methanotrophs of type II and
X, with low affinity to methane, appear in soils exposed to high levels of this gas.
In methanotrophic bacteria, enzyme methane monooxygenase (MMO), which catalyses
the oxidation of methane to methanol has been found. MMO exhibits a low substrate
specificity and metabolizes very large number of compounds including xenobiotic chemicals.
Low substrate specificity of methanotrophs has attracted attention of scientists working on
biological methods for degradation of toxic chemicals degradation (bioremediation).
1. Introduction. 2. Systematics of methanotrophs. 3. Influence of physical and chemical factors on
methane oxidation. 4. Identification of methanotrophic bacteria. 5. Heterogeneity of methanotrophic
bacteria in different environments. 6. Activity of methanotrophic bacteria in environment.
7. Interactions between methanotrophs and other bacteria. 8. Influence of land use on methane
oxidation. 9. New directions in the methanotroph resea.rch. 10. Summary