Isolation of microorganisms able to produce 1,3-propanediol and optimization of medium constituents for Klebsiella pneumoniae AJ4

Abstract

Microbial fermentation under anaerobic and microaerobic conditions has been used for the production of 1,3-propanediol (1,3-PD), a monomer used to produce polymers such as polytrimethylene terephthalate. In this study, we screened microorganisms using the high throughput screening method and isolated the Klebsiella pneumoniae AJ4 strain, which is able to produce 1,3-PD under aerobic conditions. To obtain the maximum 1,3-PD concentration from glycerol, the response surface methodology based on a central composite design was chosen to show the statistical significance of the effects of glycerol, peptone, and (NH(4))(2)SO(4) on 1,3-PD production by K. pneumoniae AJ4. The optimal culture medium factors for achieving maximum concentrations of 1,3-PD included glycerol, 108.5 g/L; peptone, 2.72 g/L; and (NH(4))(2)SO(4), 4.38 g/L. Under this optimum condition, the maximum concentration of 1,3-PD, 54.76 g/L, was predicted. A concentration of about 52.59 g/L 1,3-PD was obtained using the optimized medium during 26-h batch fermentation, a finding that agreed well with the predicted value.

Isolation and characterization of a Klebsiella pneumoniae strain from mangrove sediment for efficient biosynthesis of 1,3-propanediol

“…Usually, different strains of the same species show high diversity in physiology and metabolism due to different environmental origin. Previous reports proved that the productivity of PDO by different K. pneumoniae strains was of great disparity [12][13][14][15]. Screening of strains from various environments is a feasible method to obtain highyield PDO producer.…”

Hypothetical glycerol pathways of newly isolated strains capable of 1,3-propanediol production.

“…The number of strain isolation studies is still on the increase. Scientists are screening the natural environment for new strains capable of glycerol conversion to usable metabolites, including 1,3-PD Jungermann et al, 1973;Hiremath et al, 2011;Sattayasamitsathit et al, 2011;Gelder et al, 2012;Hong et al, 2013). As a result, new strains were obtained, among them: Trichococcus flocculiformis (Gelder et al, 2012), Klebsiella pneumoniae and Pantoea agglomerans (Rossi et al, 2012), C. butyricum .…”

Recent developments in the microbial production of 1,3-propanediol

“…Hong et al used the high throughput screening method to isolate a strain of K. pneumoniae AJ4 [27]. The new strain was able to produce PDO under aerobic condition.…”

“…Klebsiella pneumoniae AJ4 NA 52.59 0.63 2.02 [27] K. pneumoniae TUAC01 NA 66.3 NA 1.0 [28] Citrobacter freundii FMCC-B 294 (VK-19) 170 68.1 0.48 0.79 [29] Clostridium butyricum AKR102a 150 92.9 NA NA [30] Artificial breeding…”