Effects of pH, temperature and salinity on P3HB synthesis culturing the marine Rhodovulum sulfidophilum DSM-1374
- 29 Downloads
Rhodovulum sulfidophilum DSM-1374 is a potential producer of polyester when growing in phototrophic conditions. The present study investigated on a polyester product (P3HB) by culturing Rhodovulum sulfidophilum DSM-1374 in two different photobioreactors (PBR-1 and PBR-2) both with 4-L working volumes. PBR-1 is equipped with an internal rotor having 4 paddles to mix the bacterial culture while PBR-2 has an internal coil-shaped rotor. After selecting PBR-1, which best performed in the preliminary experiment, the effect of different stressing growth conditions as pH (7.0, 8.0, and 9.0), temperature (25, 30, and 35 °C), and medium salinity (1.5, 2.5, 3.5, and 4.5%) were tested. When the pH of the culture was set to 8.0, the capability of the bacterium to synthetize the polyester increased significantly reaching a concentration of 412 mg (P3HB)/L; the increase of the pH at 9.0 caused a reduction of the P3HB concentration in the culture. The medium salinity of 4.5% was the best stress-growth condition to reach the highest concentration of polyester in the culture (820 ± 50 mg (P3HB)/L) with a P3HB mass fraction in the dry biomass of 33 ± 1.5%. Stresses caused by culture temperature are another potential parameter that could increase the synthesis of P3HB.
KeywordsPhotobioreactors Rhodovulum sulfidophilum DSM-1374 Polyhydroxyalkanoate Poly(3-hydroxybutyrate) Salinity
The authors would like to thank Marco De Vito (CNR-ISE) for the support in the analysis of samples.
This study was funded by the Regione Toscana, Italy, with the Project “ROBO-IMPLANT,” Bando FAS Salute 2014 (grant number 13299).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
- Carlozzi P, Giovannelli A, Traversi ML, Touloupakis E, Di Lorenzo T (2019b) Poly-3-hydroxybutyrate and H2 production by Rhodopseudomonas sp. S16-VOGS3 grown in a new generation photobioreactor under single or combined nutrient deficiency. Int J Biol Macromol 135:821–828. https://doi.org/10.1016/j.ijbiomac.2019.05.220 CrossRefPubMedGoogle Scholar
- Carlozzi P, Pushparaj B, Degl’Innocenti A, Capperucci A (2006) Growth characteristics of Rhodopseudomonas palustris cultured outdoors, in an underwater tubular photobioreactor and investigation on photosynthetic efficiency. Appl Microbiol Biotechnol 73:789–795. https://doi.org/10.1007/s00253-006-0550-z CrossRefPubMedGoogle Scholar
- Carlozzi P, Seggiani M, Capperucci A, Tanini D, Cinelli P, Lazzeri A (2019a) Hydroxytyrosol rich-mixture from olive mill wastewater and production of green products by feeding Rhodopseudomonas sp. S16-FVPT5 with the residual effluent. J Biotechnol 295:28–36. https://doi.org/10.1016/j.jbiotec.2019.02.006 CrossRefPubMedGoogle Scholar
- Carlozzi P, Touloupakis E, Di Lorenzo T, Giovannelli A, Seggiani M, Cinelli P, Lazzeri A (2019c) Whey and molasses as inexpensive raw materials for parallel production of biohydrogen and polyesters via a two-stage bioprocess: new routes towards a circular bioeconomy. J Biotechnol 303:37–45. https://doi.org/10.1016/j.jbiotec.2019.07.008 CrossRefPubMedGoogle Scholar
- Chowdhury WQ, Idehara K, Maeda I, Umeda F, Yagi K, Miura Y, Mizoguki T (1996) Factors affecting polyhydroxybutyrate biosynthesis in the marine photosynthetic bacterium Rhodopseudomonas sp. strain W-1S. Appl Biochem Biotechnol 57(58):361–366. https://doi.org/10.1007/978-1-4612-0223-3_31 CrossRefGoogle Scholar
- CIEL (2017) Fossils, plastics, & petrochemical feedstocks. In Fueling Plastics, pp. 1–5, Center for International Environment LawGoogle Scholar
- Clemente T, Shah D, Tran M, Stark D, Padgette S, Dennis D, Brückener K, Steinbüchel A, Mitsky T (2000) Sequence of PHA synthase gene from two strains of Rhodospirillum rubrum and in vivo substrate specificity of four PHA synthases a cross two heterologous expression systems. Appl Microbiol Biotechnol 53:420–429. https://doi.org/10.1007/s002530051636 CrossRefPubMedGoogle Scholar
- Kobayashi J, Kondo A (2019) Disruption of poly (3-hydroxyalkanoate) depolymerase gene and overexpression of three poly (3-hydroxybutyrate) biosynthetic genes improve poly (3-hydroxybutyrate) production from nitrogen rich medium by Rhodobacter sphaeroides. Microb Cell Factories 18:40. https://doi.org/10.1186/s12934-019-1088-y CrossRefGoogle Scholar
- Lorrungruang C, Martthong J, Sasaki K, Noparatnaraporn N (2006) Selection of photosynthetic bacterium Rhodobacter sphaeroides 14F for polyhydroxyalkanoate production with two-stage aerobic dark cultivation. J Biosci Bioeng 102:128–131. https://doi.org/10.1263/jbb.102.128 CrossRefPubMedGoogle Scholar
- Maeda I, Chowdhury WQ, Idehara K, Yagi K, Mizoguchi T, Akano T, Miyasaka H, Furutani T, Ikuta Y, Shioji N, Miura Y (1998) Improvement of substrate conversion to molecular hydrogen by three-stage cultivation of a photosynthetic bacterium, Rhodovulum sulfidophilum. Appl Biochem Biotechnol 70-72:301–310. https://doi.org/10.1007/BF02920146 CrossRefPubMedGoogle Scholar
- Martinez GA, Bertin L, Scoma A, Rebecchi S, Braunegg G, Fava F (2015) Production of polyhydroxyalkanoates from dephenolised and fermented olive mill wastewaters by employing a pure culture of Cupriavidus necator. Biochem Eng J 97:92–100. https://doi.org/10.1016/j.bej.2015.02.015 CrossRefGoogle Scholar
- Narancic T, Scollica E, Kenny ST, Gibbons H, Carr E, Brennan L, Cagney G, Wynne K, Murphy C, Raberg M, Heinrich D, Steinbüchel A, O’Connor K (2016) Understanding the physiological roles of polyhydroxybutyrate (PHB) in Rhodospirillum rubrum S1 under aerobic chemoheterotrophic conditions. Appl Microbiol Biotechnol 100(20):8901–8912. https://doi.org/10.1007/s00253-016-7711-5 CrossRefPubMedGoogle Scholar
- Narancic T, Verstichel S, Reddy Chaganti S, Morales-Gamez L, Kenny ST, De Wilde B, Padamati RB, O’Connor KE (2018) Biodegradable plastic blends create new possibilities for end-of-life management of plastics but they are not a panacea for plastic pollution. Environ Sci Technol 52:10441–10452. https://doi.org/10.1021/acs.est.8b02963 CrossRefPubMedGoogle Scholar
- Rutkowska M, Heimowska A, Krasowska K, Janik H (2002) Biodegradability of polyethylene starch blends in sea water. Pol Int J Environ Stud 11:267–272Google Scholar