Long DNA Synthesis Service

Long DNA Synthesis service is dedicated to the precise, accurate manufacturing of exceptionally large genetic constructs, typically exceeding 5,000 base pairs (bp) and often extending well beyond 20 kb. These complex constructs include multi-gene operons, entire biosynthetic pathways, artificial chromosomes, or large genomic regions designed for synthetic genomics and complex metabolic engineering projects. Traditional gene synthesis methods often fail or become prohibitively expensive and slow when dealing with these megabase-scale fragments.

CD Biosynsis utilizes proprietary, advanced assembly technologies, such as seamless multi-fragment ligation and hierarchical assembly techniques, combined with specialized error-correction protocols. This allows us to deliver ultra-long, 100% sequence-verified DNA fragments and constructs cloned into your vector of choice. Our expertise in handling repetitive elements, highly structured sequences, and large pathway assembly ensures that your most ambitious synthetic biology designs—from microbial genome optimization to mammalian synthetic circuit construction—can be reliably manufactured and delivered.

Highlights

Key technical differentiators for our expertise in synthesizing ultra-long DNA constructs:

• Ultra-High Capacity: Routinely handle synthesis projects exceeding 20 kb and up to 50 kb , encompassing entire operons, large cassettes, and genome-scale parts.
• Advanced Assembly Technology: Proprietary hierarchical and sequence-independent DNA assembly methods minimize errors and maximize efficiency across complex multi-fragment joins.
• Complex Sequence Resolution: Specialized protocols to synthesize and stabilize regions with extensive repetitive sequences, high/low GC domains, and secondary structures that are impossible with standard PCR or assembly.
• Guaranteed Full Verification: Utilize targeted Next-Generation Sequencing (NGS) and sophisticated mapping to ensure 100% sequence accuracy across the entire long fragment, including all junctions.

Applications

Our Long DNA Synthesis is essential for cutting-edge projects requiring large genetic parts:

Synthetic & Metabolic Pathway Engineering

           

Construction of complete, multi-enzyme biosynthetic pathways and clustered regularly interspaced short palindromic repeats (CRISPR) arrays in a single construct.

Synthetic Genomics & Genome Editing

Synthesis of large DNA payloads for microbial genome reduction/expansion, or HDR donor templates for large-scale mammalian cell engineering.

DNA & RNA Vaccine Development

Manufacturing large-scale, high-purity plasmids containing complex therapeutic gene cassettes, optimized for expression and delivery.

Construction of BACs/YACs

Assembly of extremely large DNA segments for insertion into bacterial artificial chromosomes (BACs) or yeast artificial chromosomes (YACs).

Solutions

Our platform combines computational design with advanced molecular assembly techniques for ultra-long DNA:

Hierarchical Assembly Strategy

Breaking down long DNA into optimal smaller fragments and assembling them in a multi-step, verified manner to maintain high accuracy and stability.

Advanced Error Correction

Proprietary enzymatic mismatch repair and in vitro selection cycles ensure near-perfect fidelity before the final assembly step.

Seamless Cloning & Delivery

Final constructs are delivered cloned into appropriate high-capacity vectors (e.g., low-copy plasmids, BACs) with minimized sequence scar at assembly junctions.

Toxic Gene Handling

Use of specialized propagation host strains (e.g., conditional expression vectors) to stabilize and synthesize sequences that are lethal or unstable in standard E. coli strains.

Targeted NGS Verification

Deep sequencing is performed across the entire construct, with high coverage focused on junction points and difficult regions to guarantee accuracy.

Workflow

Our dedicated workflow for Long DNA Synthesis is optimized for high fidelity and scale:

• Project Design and Fragmentation: The ultra-long target sequence is computationally fragmented into an optimal set of high-quality, smaller synthesis modules (up to 5 kb each), alongside complimentary Codon Optimization.
• Module Synthesis and Initial Verification: Each module is synthesized individually using standard methods. Crucially, each intermediate module is verified by Sanger sequencing before proceeding to the next assembly step.
• Hierarchical Assembly and Cloning: The verified modules are assembled in a controlled, multi-step process (e.g., using Gibson, Golden Gate, or proprietary methods) to form the full-length construct, which is then cloned into a high-capacity vector.
• Full-Length Quality Control (NGS): The final, assembled clone undergoes rigorous full-length verification using Next-Generation Sequencing (NGS) to confirm 100% accuracy and mapping across the entire sequence length.
• Final Delivery: The sequence-verified, ultra-long plasmid DNA is purified and delivered (along with the necessary documentation, including the COA, NGS report, and vector map) ready for your downstream experiments.

We provide specialized assurance for large, complex DNA projects:

• Scale and Precision: We deliver complex constructs with guaranteed precision, saving you the immense time and resources of attempting large-scale assembly in-house.
• Technical Consultation: Dedicated technical project managers with expertise in large DNA assembly advise on sequence design, vector choice (BACs, low-copy plasmids), and stability issues.
• Phased Verification: Intermediate QC steps are built into the hierarchical assembly process, ensuring errors are corrected early, guaranteeing the fidelity of the final construct.
• Proprietary Technologies: Utilization of internal ligation-independent and error-correction methods that dramatically increase the yield and purity of constructs up to 50 kb.