Cyanobacteria as cell factories: the roles of host and pathway engineering and translational research

Jaiswal, Damini; Sahasrabuddhe, Deepti; Wangikar, Pramod P.

doi:10.1016/j.copbio.2021.09.010

Cited by 30 publications

(17 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Systems and synthetic biology approaches aim at the engineering of strains with improved photosynthetic performance based on, e.g., improved photosystems, optimal protein allocation, and/or efficient carbon concentration and fixation ( Burnap, 2015 ; Ort et al, 2015 ; Jahn et al, 2018 ; Luan et al, 2020 ; Miao et al, 2020 ; Roussou et al, 2021 ). Strategies include the reduction of antenna systems for more efficient light absorption in high-density cultures ( Kirst et al, 2014 ), attenuation of protection mechanisms ( Allahverdiyeva et al, 2015 ; Bassi and Dall'Osto, 2021 ; Kirilovsky et al, 2014 ), and streamlining of carbon, energy, and redox metabolism ( Veaudor et al, 2020 ; Roussou et al, 2021 ; Santos-Merino et al, 2021 ; Zhou et al, 2021 ; Jaiswal et al, 2022 ). Furthermore, operating costs and costs for product removal have to be considered.…”

Section: Pathway Engineeringmentioning

confidence: 99%

“…This allows biocatalyst production, regeneration, and operation at minimal economical and ecological costs in overall carbon neutral and land-saving processes. Recent results show the high potential of cyanobacteria, green algae, and other phototrophs to produce biomass ( Tsuzuki et al, 2019 ), biofuels ( Arias et al, 2021 ; Kato et al, 2022 ), chemicals ( Vavitsas et al, 2021 ; Jaiswal et al, 2022 ), and high value compounds ( Tanvir et al, 2021 ). Respective advantages and disadvantages are intensely discussed, and new strategies have been developed to overcome limitations in carbon fixation ( Batista-Silva et al, 2020 ).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Exploitation of Hetero- and Phototrophic Metabolic Modules for Redox-Intensive Whole-Cell Biocatalysis

Theodosiou

Tüllinghoff

Toepel

et al. 2022

Front. Bioeng. Biotechnol.

View full text Add to dashboard Cite

The successful realization of a sustainable manufacturing bioprocess and the maximization of its production potential and capacity are the main concerns of a bioprocess engineer. A main step towards this endeavor is the development of an efficient biocatalyst. Isolated enzyme(s), microbial cells, or (immobilized) formulations thereof can serve as biocatalysts. Living cells feature, beside active enzymes, metabolic modules that can be exploited to support energy-dependent and multi-step enzyme-catalyzed reactions. Metabolism can sustainably supply necessary cofactors or cosubstrates at the expense of readily available and cheap resources, rendering external addition of costly cosubstrates unnecessary. However, for the development of an efficient whole-cell biocatalyst, in depth comprehension of metabolic modules and their interconnection with cell growth, maintenance, and product formation is indispensable. In order to maximize the flux through biosynthetic reactions and pathways to an industrially relevant product and respective key performance indices (i.e., titer, yield, and productivity), existing metabolic modules can be redesigned and/or novel artificial ones established. This review focuses on whole-cell bioconversions that are coupled to heterotrophic or phototrophic metabolism and discusses metabolic engineering efforts aiming at 1) increasing regeneration and supply of redox equivalents, such as NAD(P/H), 2) blocking competing fluxes, and 3) increasing the availability of metabolites serving as (co)substrates of desired biosynthetic routes.

show abstract

Section: Pathway Engineeringmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Exploitation of Hetero- and Phototrophic Metabolic Modules for Redox-Intensive Whole-Cell Biocatalysis

Theodosiou

Tüllinghoff

Toepel

et al. 2022

Front. Bioeng. Biotechnol.

View full text Add to dashboard Cite

show abstract

“…However, all of these systems report a range of shortcomings which prevent them from broad application and fast implementation, the most prominent being the challenges associated with cloning and expression of the target enzyme in the applied photoautotrophic organisms. [ 31 , 32 , 33 ] Especially the long period (months) required for the introduction of a target gene in a photoautotrophic host excludes a fast variation and investigation of different expression systems, promotors, constructs, and also a screening of enzyme panels or enzyme variants. Further issues include the problematic heterologous expression of enzymes that are toxic to the cells metabolism or a limited transfer of the substrate or product through the cell‐membrane of the living organism.…”

Section: Introductionmentioning

confidence: 99%

Transmembrane Shuttling of Photosynthetically Produced Electrons to Propel Extracellular Biocatalytic Redox Reactions in a Modular Fashion

et al. 2022

View full text Add to dashboard Cite

Many biocatalytic redox reactions depend on the cofactor NAD(P)H, which may be provided by dedicated recycling systems. Exploiting light and water for NADPH-regeneration as it is performed, e.g. by cyanobacteria, is conceptually very appealing due to its high atom economy. However, the current use of cyanobacteria is limited, e.g. by challenging and timeconsuming heterologous enzyme expression in cyanobacteria as well as limitations of substrate or product transport through the cell wall. Here we establish a transmembrane electron shuttling system propelled by the cyanobacterial photosynthesis to drive extracellular NAD(P)H-dependent redox reactions. The modular photo-electron shuttling (MPS) overcomes the need for cloning and problems associated with enzyme-or substrate-toxicity and substrate uptake. The MPS was demonstrated on four classes of enzymes with 19 enzymes and various types of substrates, reaching conversions of up to 99 % and giving products with > 99 % optical purity.

show abstract

“…There are many factors controlling the generation of fully segregated mutants, which include cyanobacterial strain background, lab conditions, and types of mutations ( Lea-Smith et al, 2016 ). Compared to heterotrophic bacteria, the growth rate of cyanobacteria is slow ( Burnap, 2015 ; Jaiswal et al, 2022 ), especially in solid medium ( Hayashi et al, 2011 ; Gao et al, 2020 ), which further confers a challenge for cyanobacterial transformation. Previous studies have tried to determine the optimum conditions for the growth of multiple cyanobacteria on solid media.…”

Section: Introductionmentioning

confidence: 99%

Generation of miniploid cells and improved natural transformation procedure for a model cyanobacterium Synechococcus elongatus PCC 7942

et al. 2022

View full text Add to dashboard Cite

The biotechnologically important and naturally transformable cyanobacterium, Synechococcus elongatus PCC 7942, possesses multiple genome copies irrespective of its growth rate or condition. Hence, segregating mutations across all genome copies typically takes several weeks. In this study, Synechococcus 7942 cultivation on a solid growth medium was optimised using different concentrations of agar, the addition of antioxidants, and overexpression of the catalase gene to facilitate the rapid acquisition of colonies and fully segregated lines. Synechococcus 7942 was grown at different temperatures and nutritional conditions. The miniploid cells were identified using flow cytometry and fluorimetry. The natural transformation was carried out using miniploid cells and validated with PCR and high performance liquid chromatography (HPLC). We identified that 0.35% agar concentration and 200 IU of catalase could improve the growth of Synechococcus 7942 on a solid growth medium. Furthermore, overexpression of a catalase gene enhanced the growth rate and supported diluted culture to grow on a solid medium. Our results reveal that high temperature and phosphate-depleted cells contain the lowest genome copies (2.4 ± 0.3 and 1.9 ± 0.2) and showed the potential to rapidly produce fully segregated mutants. In addition, higher antibiotic concentrations improve the selection of homozygous transformants while maintaining similar genome copies at a constant temperature. Based on our observation, we have an improved cultivation and natural transformation protocol for Synechococcus 7942 by optimising solid media culturing, generating low-ploidy cells that ultimately reduced the time required for the complete segregation of engineered lines.

show abstract

Cyanobacteria as cell factories: the roles of host and pathway engineering and translational research

Cited by 30 publications

References 62 publications

Exploitation of Hetero- and Phototrophic Metabolic Modules for Redox-Intensive Whole-Cell Biocatalysis

Exploitation of Hetero- and Phototrophic Metabolic Modules for Redox-Intensive Whole-Cell Biocatalysis

Transmembrane Shuttling of Photosynthetically Produced Electrons to Propel Extracellular Biocatalytic Redox Reactions in a Modular Fashion

Generation of miniploid cells and improved natural transformation procedure for a model cyanobacterium Synechococcus elongatus PCC 7942

Contact Info

Product

Resources

About