Metabolic potential of the moderate halophile Yangia sp. ND199 for co‐production of polyhydroxyalkanoates and exopolysaccharides

Abstract

Yangia sp. ND199 is a moderately halophilic bacterium isolated from mangrove samples in Northern Vietnam, which was earlier reported to grow on several sugars and glycerol to accumulate poly(hydroxyalkanoates) (PHA). In this study, the potential of the bacterium for co‐production of exopolysaccharides (EPS) and PHA was investigated. Genome sequence analysis of the closely related Yangia sp. CCB‐M3 isolated from mangroves in Malaysia revealed genes encoding enzymes participating in different EPS biosynthetic pathways. The effects of various cultivation parameters on the production of EPS and PHA were studied. The highest level of EPS (288 mg/L) was achieved using sucrose and yeast extract with 5% NaCl and 120 mM phosphate salts but with modest PHA accumulation (32% of cell dry weight, 1.3 g/L). Growth on fructose yielded the highest PHA concentration (85% of CDW, 3.3 g/L) at 90 mM phosphate and higher molecular weight EPS at 251 mg/L yield at 120 mM phosphate concentration. Analysis of EPS showed a predominance of glucose, followed by fructose and galactose, and minor amounts of acidic sugars.

Exopolysaccharides Production by Cultivating a Bacterial Isolate from the Hypersaline Environment of Salar de Uyuni (Bolivia) in Pretreatment Liquids of Steam-Exploded Quinoa Stalks and Enzymatic Hydrolysates of Curupaú Sawdust

“…All the cultivations were performed in 50-mL bottles containing 22 mL of the medium and inoculated with 3 mL of a cell suspension with initial OD 620 of 2.1. The bottles were sealed with rubber caps, and the cultivation was run at 30 • C and 100 rpm for 48 h. Samples were withdrawn at regular intervals for analyses of cell growth and EPS production as previously reported [35,36]. All experiments were carried out in duplicates.…”

“…Cell growth was determined by measuring the optical density (OD) at 620 nm with a spectrophotometer (UV 1800, Shimadzu, Japan) as previously reported [35]. Culture samples (500 µL) were centrifuged at 16,900× g for 5 min, diluted with 4.5 mL of acidified water (with H 2 SO 4 ), and stirred for 10 s. Each sample was filtered through a 20 µm filter, and sugar consumption was analyzed by HPLC using an Aminex HPX-87H column (Bio-Rad, Hercules, CA, USA) coupled to a Prominence HPLC system (Shimadzu Corp., Kyoto, Japan), equipped with a CBM-20A system controller, an isocratic pump (LC-30AD), a refractive index detector (RID-20A), a column oven (CTO-10 ASVP), a degasser (DGU-20A), and an autosampler (SIL-30AC).…”

“…For instance, the signal at 2562 cm −1 can be assigned to the C-H stretching of methyl or methylene groups of hexoses or deoxyhexoses [36]. A peak in the region of 1644 cm −1 related to carboxylic acids, can be associated with the higher water retention capacity of the polysaccharide [35,45]. The band around 1127 cm −1 is a characteristic peak of uronic or acetyl esters in polysaccharides [46].…”

Influence of the Carbon and Nitrogen Sources on Diabolican Production by the Marine Vibrio diabolicus Strain CNCM I-1629

“…Firstly, we tested the impact of various carbon sources on EPS yield and MW ( Figure 2 a,b). Ammonium chloride (100 mM) was chosen as the nitrogen source according to other studies [ 30 , 31 , 32 ]. Various carbon sources were used: glucose, sucrose, lactose, lactate, glycerol, and mannitol at 30 g L −1 .…”

Coproduction of 5-Aminovalerate and δ-Valerolactam for the Synthesis of Nylon 5 From L-Lysine in Escherichia coli

“…Few examples are the simultaneous synthesis of 5AVA and glutarate by Corynebacterium glutamicum ( Rohles et al, 2016 ; Haupka et al, 2020 ), β-glucan and pullulan by engineering Aureobasidium pullulans ( Wang G.-L. et al, 2020 ), acetoin and succinic acid by Enterobacter cloacae ( Su et al, 2021 ), polyhydroxyalkanoates and exopolysaccharides by Yangia sp. ND199 ( Romero Soto et al, 2021 ), and xylitol and ethanol by yeast strains ( Shankar et al, 2020 ). Lopez-Hidalgo et al reported that the engineered strain increased 30% the coproduction of ethanol and hydrogen used wheat straw and corn stover as feedstock ( Lopez-Hidalgo et al, 2021 ).…”