Nesterenkonia sp. strain F, a halophilic bacterium producing acetone, butanol and ethanol under aerobic conditions

Abstract

The moderately halophilic bacterium Nesterenkonia sp. strain F, which was isolated from Aran-Bidgol Lake (Iran), has the ability to produce acetone, butanol, and ethanol (ABE) as well as acetic and butyric acids under aerobic and anaerobic conditions. This result is the first report of ABE production with a wild microorganism from a family other than Clostridia and also the first halophilic species shown to produce butanol under aerobic cultivation. The cultivation of Nesterenkonia sp. strain F under anaerobic conditions with 50 g/l of glucose for 72 h resulted in the production of 105 mg/l of butanol, 122 mg/l of acetone, 0.2 g/l of acetic acid, and 2.5 g/l of butyric acid. Furthermore, the strain was cultivated on media with different glucose concentrations (20, 50, and 80 g/l) under aerobic and anaerobic conditions. Through fermentation with a 50 g/l initial glucose concentration under aerobic conditions, 66 mg/l of butanol, 125 mg/l of acetone, 291 mg/l of ethanol, 5.9 g/l of acetic acid, and 1.2 g/l of butyric acid were produced. The enzymes pertaining to the fermentation pathway in the strain were compared with the enzymes of Clostridium spp., and the metabolic pathway of fermentation used by Nesterenkonia sp. strain F was investigated.

Efficient butanol production under aerobic conditions by coculture of Clostridium acetobutylicum and Nesterenkonia sp. strain F

“…The Nesterenkonia sp. strain F was cultivated in petri‐dish consisting of (g/L): NaCl, 10; MgCl 2 , 7; MgSO 4 , 9.6; CaCl 2 , 0.36; KCl, 2; NaHCO 3 , 0.06; NaBr, 0.026; peptone, 5; yeast extract, 10; and glucose, 20 (Amiri et al, ; Amoozegar, Samareh‐Abolhasani, Shafiei, Didari, & Hamedi, ). For preculture, a modified medium containing (g/L): MgCl 2 , 0.7; MgSO4, 0.9; peptone, 3; yeast extract, 1; and glucose, 50 was used to adapt the Nesterenkonia for the next stage.…”

“…C. acetobutylicum and C. beijerinckii are highly sensitive to the external environment, for example, oxygen concentration, osmotic pressure, and phenolic compounds. In our previous study, it was found that Clostridia are not the only microorganisms for biobutanol production (Amiri et al, 2016). It was demonstrated that a wild bacterium from Nesterenkonia genus could produce butanol and butyric acid along with acetone and acetic acid even in aerobic and halophilic conditions.…”

“…Nesterenkonia sp. strain F has been known for its ability to produce solvent‐stable extracellular enzymes in relatively harsh conditions, for example, high osmotic pressure (Amiri et al, ; Shafiei, Ziaee, & Amoozegar, ). The excreted enzymes can endure solvents that are released by Clostridia in the media, and degrade different substrates into fermentable monomers (Al‐shorgani, Khalil, Ali, & Hamid, ).…”

Recent Development of Extremophilic Bacteria and Their Application in Biorefinery

“…A halophilic bacterium Nesterenkonia sp. F can tolerate organic solvents and produce α-amylase, and it is the only wild bacterium that can produce butanol and ethanol except Clostridia (Amiri et al, 2016). Many enzymes, such as α-amylase, β-amylase, glucoamylase, lipase, esterase, hemicellulose, and ligninase of a halophilic and halotolerant bacterial origin hold potential industrial applications, such as bioethanol, biodiesel, or fatty acids production using renewable resources (Schreck and Grunden, 2014;Elmansy et al, 2018;Amoozegar et al, 2019).…”

Genomic and metabolic insights into solvent production by Thermoanaerobacterium thermosaccharolyticum GSU5

“…Although most butanol producers are strictly anaerobic, the halophile Nesterenkonia sp. strain F has also been reported to produce ABE from glucose under aerobic conditions (Amiri et al, 2016).…”