Production of Phytochromes by High-Cell-Density E. coli Fermentation

2019 ◽  
Vol 8 (10) ◽  
pp. 2442-2450 ◽  
Author(s):  
Maximilian Hörner ◽  
Karl Gerhardt ◽  
Pavel Salavei ◽  
Philipp Hoess ◽  
Daniel Härrer ◽  
...  
2013 ◽  
Vol 97 (9) ◽  
pp. 3893-3900 ◽  
Author(s):  
Odile Francesca Restaino ◽  
Ujjwal Bhaskar ◽  
Priscilla Paul ◽  
Lingyun Li ◽  
Mario De Rosa ◽  
...  

2016 ◽  
Author(s):  
Wenfa Ng ◽  
Yen-Peng Ting

Microbes for environmental research should be cultured in growth media with characteristics (e.g., pH, ionic strength, and organic and ionic composition) as close to their original habitat as possible. Additionally, the medium should also enable high cell density to be obtained - needed for providing sufficient cells in subsequent experiments. This in-progress report describes the formulation of a medium with an environmentally-relevant composition (lack of complex organics), and that allows aerobic high cell density cultivation of Escherichia coli DH5α in shake flasks. The formulated medium comprises four components: a buffer system (K2HPO4: 12.54 g/L and KH2PO4: 2.31 g/L), vitamins (yeast extract: 12.0 g/L), salts (NaCl: 5.0 g/L and MgSO4: 0.24 g/L), and carbon and nitrogen sources (D-Glucose: 6.0 g/L and NH4Cl: 1.5 g/L). Notable characteristics of this medium were: high capacity phosphate buffer system (89 mM phosphate); 1:1 molar ratio between D-Glucose and NH4Cl; and yeast extract providing trace elements and a secondary carbon and nitrogen source. Growth experiments revealed that an OD600nm of 9 was attained after 24 hours of cultivation at 37 oC. Glucose and NH4Cl serve as primary carbon and nitrogen sources for this phase of growth. After 48 hours, the OD600nm reached 11, where carbohydrates, lipids and proteins in yeast extract provided the nutrients for biomass formation. Broth’s pH varied between 5.5 and 7.8 during cultivation, which was in the range conducive for E. coli growth. In comparison, the OD600nm of E. coli reached 1.4, 3.2, and 9.2 in three commonly used complex media; Nutrient Broth, LB Lennox, and Tryptic Soy Broth, respectively, over 48 hours under identical culture conditions. In addition, the formulated medium was able to maintain a large viable cell population for a longer period of time (three days) compared to Tryptic Soy Broth. Thus, preliminary data suggested that the formulated medium holds potential for use as a high cell density aerobic growth medium for Gram-negative bacteria.


2006 ◽  
Vol 41 (4) ◽  
pp. 920-924 ◽  
Author(s):  
Toru Matsui ◽  
Naoya Shinzato ◽  
Haruto Yokota ◽  
Joji Takahashi ◽  
Seigo Sato

2016 ◽  
Author(s):  
Wenfa Ng ◽  
Yen-Peng Ting

Sufficient quantities of cells of consistent characteristics are needed for studying biological processes (at the population level) in many areas of applied microbiology. However, generating the requisite biomass by cell culture is usually the rate-limiting step of a project given the relatively low biomass yield of many commercial culture media in shake flasks. This work reports the formulation of a semi-defined medium that enabled aerobic high cell density cultivation of Escherichia coli DH5α (ATCC 53868) in shake flasks. The formulated medium (FM) comprises: a buffer system (K2HPO4: 12.54 g/L and KH2PO4: 2.31 g/L); vitamins and trace elements (yeast extract: 12.0 g/L); salts (NaCl: 5.0 g/L and MgSO4: 0.24 g/L); and carbon and nitrogen sources (D-Glucose: 6.0 g/L and NH4Cl: 1.5 g/L). Notable characteristics of this medium are: high buffer capacity (89 mM phosphate), 1:1 molar ratio between D-Glucose and NH4Cl, and yeast extract providing trace elements and a secondary source of carbon and nitrogen. Preliminary data revealed that an OD600nm of 9 was attained after 24 hours of cultivation at 37 oC, with glucose and NH4Cl as the main nutrients. At 48 hours, the OD600nm reached a maximum value of 11 with yeast extract providing the necessary nutrients for cell growth and biomass formation. The broth’s pH varied between 5.5 and 7.8 during cultivation. For comparison, the maximum OD600nm of E. coli grown in three commonly used complex media: Nutrient Broth, LB Lennox, and Tryptic Soy Broth (TSB) were 1.4, 3.2 and 9.2, respectively, under identical culture conditions. Finally, FM maintained the viability of a larger population of cells for three days - compared to a population collapse observed in TSB after one day. Collectively, the present findings suggested that the formulated medium might find use as a high cell density aerobic growth medium for E. coli in shake flasks. Part 2 of this work describes improvements in medium performance - specifically, higher cell yield as well as a shorter diauxic lag phase and total culture period – achieved through a small reduction in D-Glucose and NH4Cl concentrations in the medium composition. An abstract preprint of Part 2 is available at https://peerj.com/preprints/117/


2017 ◽  
Author(s):  
Wenfa Ng

Sufficient quantities of cells of consistent characteristics are needed for studying biologicalprocesses (at the population level ) in many areas of applied microbiology. However, generating the requisite biomass by cell culture is usually the rate-limiting step of a project given the relatively low biomass yield of many commercial culture media in shake flask culture systems. This work reports the formulation of a semi-defined medium that enabled aerobic high cell density cultivation of Escherichia coli DH5α (ATCC 53868) in shake flasks. The formulated medium (FM) comprises: a buffer system (K2HPO4 : 12.54 g/L and KH2 PO4 : 2.31 g/L); vitamins and trace elements (yeast extract: 12.0 g/L); salts (NaCl: 5.0 g/L and MgSO4 : 0.24 g/L); and carbon and nitrogen sources (D-Glucose: 6.0 g/L and NH4Cl: 1.5 g/L). Notable characteristics of this medium are: high buffer capacity (89 mM phosphate), 1:1 molar ratio between D-Glucose and NH4Cl, and yeast extract providing trace elements and a secondary source of carbon and nitrogen. Preliminary data revealed an OD 600nm of 9 after 24 hours of cultivation at 37 oC, presumably with glucose and NH4Cl as the main nutrients. At 48 hours, an OD 600nm of 11 was attained with yeast extract providing the necessary nutrients for cell growth and biomass formation. The broth’s pH varied between 5.5 and 7.8 during cultivation. On the other hand, the maximum OD 600nm of E. coli grown in three commonly used complex media: Nutrient Broth, LB Lennox, and Tryptic Soy Broth (TSB) were 1.4, 3.2 and 9.2, respectively, under identical culture conditions. Finally, FM maintained the viability of a larger population of cells for three days, compared to a population collapse in TSB broth after one day. Collectively, the results suggested that the formulated medium might find use as a high cell density aerobic growth medium for E. coli in shake flasks. Part 2 of this work describes improvements in medium performance ; specifically, higher cell yield as well as a shorter diauxic lag phase and total culture period achieved through a small reduction in D-Glucose and NH4Cl concentrations in the medium composition. An abstract preprint of Part 2 is available at https://peerj.com/preprints/117/


Sign in / Sign up

Export Citation Format

Share Document