Isolation and Characterization of 1-Hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexene-1-acetic Acid, a Metabolite in Bacterial Transformation of Abscisic Acid

Oleg S Yuzikhin; Alexander I Shaposhnikov; Tatyana A Konnova; Darya S Syrova; Hamza Hamo; Taras S Ermekkaliev; Valerii P Shevchenko; Konstantin V Shevchenko; Natalia E Gogoleva; Anton A Nizhnikov; Vera I Safronova; Alexander A Kamnev; Andrey A Belimov; Yuri V Gogolev

doi:10.3390/biom12101508

Isolation and Characterization of 1-Hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexene-1-acetic Acid, a Metabolite in Bacterial Transformation of Abscisic Acid

Biomolecules. 2022 Oct 18;12(10):1508. doi: 10.3390/biom12101508.

Authors

Oleg S Yuzikhin^{1

2}, Alexander I Shaposhnikov¹, Tatyana A Konnova³, Darya S Syrova¹, Hamza Hamo⁴, Taras S Ermekkaliev⁴, Valerii P Shevchenko⁵, Konstantin V Shevchenko⁵, Natalia E Gogoleva^{3

4}, Anton A Nizhnikov^{1

6}, Vera I Safronova¹, Alexander A Kamnev⁷, Andrey A Belimov¹, Yuri V Gogolev^{3

4}

Affiliations

¹ All-Russia Research Institute for Agricultural Microbiology, Podbelskogo sh. 3, Pushkin, 196608 Saint Petersburg, Russia.
² All-Russian Research Institute of Plant Protection, Podbelskogo sh. 3, Pushkin, 196608 Saint Petersburg, Russia.
³ Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of the Russian Academy of Sciences", 420111 Kazan, Russia.
⁴ Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, Kremlevskaya Street 18, 420008 Kazan, Russia.
⁵ Institute of Molecular Genetics, Russian Academy of Sciences, Akademika Kurchatova Square 2, 123182 Moscow, Russia.
⁶ Faculty of Biology, Saint Petersburg State University, University Embankment 7/9, 199034 Saint Petersburg, Russia.
⁷ Institute of Biochemistry and Physiology of Plants and Microorganisms, Subdivision of the Federal State Budgetary Research Institution Saratov Federal Scientific Center of the Russian Academy of Sciences, 410049 Saratov, Russia.

Abstract

We report the discovery of a new abscisic acid (ABA) metabolite, found in the course of a mass spectrometric study of ABA metabolism by the rhizosphere bacterium Rhodococcus sp. P1Y. Analogue of (+)-ABA, enriched in tritium in the cyclohexene moiety, was fed in bacterial cells, and extracts containing radioactive metabolites were purified and analyzed to determine their structure. We obtained mass spectral fragmentation patterns and nuclear magnetic resonance spectra of a new metabolite of ABA identified as 1-hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexene-1-acetic acid, which we named rhodococcal acid (RA) and characterized using several other techniques. This metabolite is the second bacterial ABA degradation product in addition to dehydrovomifoliol that we described earlier. Taken together, these data reveal an unknown ABA catabolic pathway that begins with side chain disassembly, as opposed to the conversion of the cyclohexene moiety in plants. The role of ABA-utilizing bacteria in interactions with other microorganisms and plants is also discussed.

Keywords: 1-hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexene-1-acetic acid; NMR spectrometry; Rhodococcus; abscisic acid; microbial metabolite; phytohormones; rhizosphere; rhodococcal acid.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Abscisic Acid* / metabolism
Acetic Acid*
Plant Extracts
Transformation, Bacterial
Tritium

Substances

Abscisic Acid
Acetic Acid
Tritium
Plant Extracts

Grants and funding

This research was funded by the Russian Science Foundation. Most of the work was done with support through grant no. 17-14-01363; detailed determination of the rhodococcal acid structure using IT TOF mass-spectrometer was done with support through grant no. 19-16-00097; transcriptomic studies of Rhodococcus genes activated in the presence of ABA were done with support through grant no. 22-14-00317.