Shewanella Gene Editing Services

Shewanella Gene Editing Services

1. Research Background

Among the genus Shewanella, the model strain Shewanella oneidensis MR-1 is the best-studied type strain. It is a Gram-negative bacterium with excellent extracellular electron transfer (EET) capability. Its unique respiratory chain allows it to utilize various insoluble metal oxides (e.g., iron and manganese oxides) or electrodes as terminal electron acceptors, exhibiting promising application potential in biogeochemical cycling, environmental remediation, and bioenergy represented by microbial fuel cells.

As a classic model organism for investigating microbial electrochemistry, biofilm formation, and heavy metal transformation mechanisms, Shewanella requires precise and efficient genetic manipulation to decipher its metabolic networks and improve its practical application performance.

2. Strain Characteristics and Biological Background

(1) Gram staining property Shewanella is Gram-negative and possesses a typical outer membrane structure.

(2) Physical and physiological featuresCells are rod-shaped and motile, generally with a single polar flagellum. A prominent feature is the high abundance of c-type cytochromes and a distinctive electron transfer chain responsible for extracellular electron transfer. Members of this genus are facultative anaerobes: they carry out aerobic respiration under oxic conditions, and can alternatively use diverse metal ions or organic compounds as electron acceptors for anaerobic respiration in anoxic environments.

(3) Ecological and industrial significance Shewanella is widely distributed in aquatic sediments and soil habitats. It possesses great application value in environmental remediation (e.g., reductive detoxification of heavy metals such as Cr(VI) and U(VI)), anode power generation in microbial fuel cells, biosensor development, and the construction of synthetic biology chassis strains.

3. Established Gene Editing Strategies

Efficient genetic tools are indispensable for revealing the molecular mechanisms underlying the superior extracellular electron transfer capacity of Shewanella and advancing its applications in environmental remediation and bioenergy. Early research was constrained by low transformation efficiency; nevertheless, multiple mature editing strategies have now been established and widely adopted. The mainstream approaches reported in the literature are summarized as follows:

3.1 Novel Recombineering System

This system utilizes recombinases derived from Shewanella-infecting bacteriophages. It mediates homologous recombination between ssDNA and the chromosomal target locus, enabling precise gene knockout and site-directed point mutation.

3.2 CRISPR/Cas System

Guided by sgRNA, nucleases such as Cas9 and Cas12a introduce specific double-strand breaks at target genomic sites. Host endogenous DNA repair machinery subsequently repairs the breaks, achieving targeted gene knockout, large-fragment deletion and site-specific gene integration.

3.3 Traditional Homologous Recombination

Commonly implemented with suicide plasmids or shuttle plasmids, this strategy relies on upstream and downstream homology arms to accomplish precise base substitution and scarless genome editing.

4. Core Application Areas

(1) Environmental bioremediation and geochemical researchKnockout and targeted optimization of key genes in metal reduction pathways (e.g., the Mtr pathway) to clarify EET mechanisms, and to engineer superior strains with enhanced heavy metal reduction and organic pollutant degradation abilities.

(2) Microbial electrochemistry and bioenergyGenomic integration and overexpression of key c-type cytochrome genes to improve power generation efficiency; editing of biofilm regulatory genes to enhance bacterial colonization on electrode surfaces.

(3) Synthetic biology and biomanufacturingRedesign of central metabolic pathways to customize carbon source utilization and high-value chemical biosynthesis, enabling the development of Shewanella as an efficient microbial cell factory; construction of whole-cell biosensors for environmental monitoring.

(4) Fundamental mechanism researchPrecise knockout and point mutation of genes associated with quorum sensing, cell motility and biofilm formation, to dissect the molecular regulatory networks governing environmental adaptation and survival.

5. Project Workflow and Result Validation

We provide end-to-end services from experimental design to strain delivery, guaranteeing the accuracy of genome-edited strains:

(1) Experimental design and vector construction: Design custom knockout and knock-in vectors targeting genes of interest.

(2) Bacterial transformation and positive strain screening: Overcome the inherent technical bottleneck of low transformation efficiency in Shewanella.

(3) Dual molecular validation: Positive mutant strains are strictly verified by PCR combined with Sanger sequencing.

6. Gene Editing Service Portfolio

6.1 Core Services

(1) Gene knockout / gene inactivation: Precise deletion or disruption of target genes for gene functional research and defective strain construction.

(2) Gene knock-in / overexpression: Site-specific insertion of reporter genes (e.g., fluorescent proteins, enzyme tags) and exogenous functional genes; construction of overexpression strains using strong constitutive promoters.

(3) Site-directed point mutation / genome modification: Introduction of defined point mutations for natural variation simulation, antibiotic resistance mechanism study and protein functional characterization.

(4) Multi-gene combinatorial editing: Sequential or simultaneous editing of multiple genes to support the construction of complex engineered strains.

Figure 1 Schematic Diagram of Project Workflow

6.2 Technical Advantages

(1) High editing success rate: Optimized transformation and genome-editing protocols tailored for different Shewanella strains.

(2) Fully customized solutions: Strategy design based on your research objectives, including biofilm regulation, virulence study and antibiotic resistance profiling.

(3) One-stop full-process validation: Integrated services covering scheme design, vector construction, transformation, strain screening and genotypic identification.

7. Case Study

We have delivered reliable gene editing services for prestigious universities, research institutions and biotechnology enterprises worldwide.

A representative case is presented below:

Case: High-efficiency Transformation System Establishment for Shewanella Project Overview: Optimized chemical/electro-transformation protocols to establish a robust high-efficiency transformation platform for Shewanella.

Figure 2 Sequencing verification confirmed successful plasmid transformation into host cells.

8. References

[1] Heidelberg JF, Paulsen IT, Nelson KE, et al. Genome sequence of the dissimilatory metal ion-reducing bacterium Shewanella oneidensis. Nat Biotechnol. 2002.

[2] Fredrickson JK, Romine MF, Beliaev AS, et al. Towards environmental systems biology of Shewanella. Nat Rev Microbiol. 2008.

[3] M S Donnenberg,J B Kaper.(1991).Construction of an eae deletion mutant of enteropathogenic Escherichia coli by using a positive-selection suicide vector.[J]. Infection and immunity.

Partner with Us

By partnering with us, you will work with an experienced and professional team specialized in microbial gene editing. We support your academic research and industrial projects with solid technical expertise, standardized workflows and efficient communication.

Inquire now to get your customized editing scheme and official quotation.