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Physiological responses to nitrogen availability in Hydrogenovibrio marinus
Brandon C Enalls1, Lindsay Van House1, Jamia Shepard1
1Center for Biomolecular Science and Engineering, US Naval Research Laboratory, Washington, DC, USA.
Microbiology Spectrum
|June 15, 2026
Summary
Microbes adapt to nutrient changes using energy storage or biofilms. This study shows Hydrogenovibrio marinus grows better with ammonium and forms biofilms at low ammonium levels, aiding survival and biotechnology.
Area of Science:
- Microbial physiology and adaptation
- Marine microbiology
- Chemolithoautotrophic metabolism
Background:
- Microorganisms adapt to nutrient availability changes for survival.
- Glycogen accumulation and biofilm formation are key microbial adaptation strategies.
- Understanding these processes is vital for biotechnological applications.
Purpose of the Study:
- To investigate the response of Hydrogenovibrio marinus to varying nitrogen availability.
- To assess the impact of ammonium and urea concentrations on growth, substrate uptake, glycogen production, and biofilm formation.
- To elucidate the ecophysiology of marine chemolithoautotrophs concerning nitrogen.
Main Methods:
- Culturing Hydrogenovibrio marinus with different nitrogen sources (ammonium, urea) at varying concentrations.
- Measuring growth rates and substrate uptake.
- Quantifying glycogen production and observing biofilm formation.
Main Results:
- Growth was generally more robust with ammonium compared to urea.
- Nitrogen source and concentration influenced growth and gaseous substrate uptake.
- Low ammonium concentration (0.1 g NH4-N/L) induced robust biofilm formation in H. marinus.
Conclusions:
- Nitrogen availability significantly impacts the growth and survival strategies of H. marinus.
- The newly observed biofilm formation at low ammonium highlights an adaptive survival mechanism.
- Findings advance the understanding of marine chemolithoautotroph ecophysiology for potential CO2 valorization.
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