Publications

• An indoleacetate-CoA ligase and a phenylsuccinyl-CoA transferase involved in anaerobic metabolism of auxin.

  Schuehle K., Nies J., Heider J.

  The plant hormone auxin (indoleacetate) is anaerobically degraded by the Betaproteobacterium Aromatoleum aromaticum. We report here on a CoA ligase (IaaB) and a CoA-transferase (IaaL) which are encoded in the apparent substrate-induced iaa operon containing genes for indoleacetate degradation. Iaa ... >> More

  The plant hormone auxin (indoleacetate) is anaerobically degraded by the Betaproteobacterium Aromatoleum aromaticum. We report here on a CoA ligase (IaaB) and a CoA-transferase (IaaL) which are encoded in the apparent substrate-induced iaa operon containing genes for indoleacetate degradation. IaaB is a highly specific indoleacetate-CoA ligase which activates indoleacetate to the CoA-thioester immediately after uptake into the cytoplasm. This enzyme only activates indoleacetate and some closely related compounds such as naphthylacetate, phenylacetate and indolepropionate, and is inhibited by high concentrations of substrates, and by the synthetic auxin compound 2,4-dichlorophenoxyacetate, which does not serve as substrate. IaaL is a CoA-transferase recognizing several C4-dicarboxylic acids, such as succinate, phenylsuccinate or benzylsuccinate and their CoA-thioesters, but only few monocarboxylic acids and no C3-dicarboxylic acids such as benzylmalonate. The enzyme shows no stereospecific discrimation of the benzylsuccinate enantiomers. Moreover, benzylsuccinate is regiospecifically activated to 2-benzylsuccinyl-CoA, whereas phenylsuccinate is converted to an equal mixture of both regioisomers (2- and 3-phenylsuccinyl-CoA). The identification of these two enzymes allows us to set up a modified version of the metabolic pathway of anaerobic indoleacetate degradation and to investigate the sequences databases for the occurrence and distribution of this pathway in other microorgansisms. << Less

  Environ. Microbiol. 18:3120-3132(2016) [PubMed] [EuropePMC]

  This publication is cited by 13 other entries.

• Aryl Coenzyme A Ligases, a Subfamily of the Adenylate-Forming Enzyme Superfamily.

  Arnold M.E., Kaplieva-Dudek I., Heker I., Meckenstock R.U.

  Aryl coenzyme A (CoA) ligases belong to class I of the adenylate-forming enzyme superfamily (ANL superfamily). They catalyze the formation of thioester bonds between aromatic compounds and CoA and occur in nearly all forms of life. These ligases are involved in various metabolic pathways degrading ... >> More

  Aryl coenzyme A (CoA) ligases belong to class I of the adenylate-forming enzyme superfamily (ANL superfamily). They catalyze the formation of thioester bonds between aromatic compounds and CoA and occur in nearly all forms of life. These ligases are involved in various metabolic pathways degrading benzene, toluene, ethylbenzene, and xylene (BTEX) or polycyclic aromatic hydrocarbons (PAHs). They are often necessary to produce the central intermediate benzoyl-CoA that occurs in various anaerobic pathways. The substrate specificity is very diverse between enzymes within the same class, while the dependency on Mg²⁺, ATP, and CoA as well as oxygen insensitivity are characteristics shared by the whole enzyme class. Some organisms employ the same aryl-CoA ligase when growing aerobically and anaerobically, while others induce different enzymes depending on the environmental conditions. Aryl-CoA ligases can be divided into two major groups, benzoate:CoA ligase-like enzymes and phenylacetate:CoA ligase-like enzymes. They are widely distributed between the phylogenetic clades of the ANL superfamily and show closer relationships within the subfamilies than to other aryl-CoA ligases. This, together with residual CoA ligase activity in various other enzymes of the ANL superfamily, leads to the conclusion that CoA ligases might be the ancestral proteins from which all other ANL superfamily enzymes developed. << Less

  Appl Environ Microbiol 87:e0069021-e0069021(2021) [PubMed] [EuropePMC]

  This publication is cited by 8 other entries.