AccuBase® Base Editor

• No double-strand DNA breaks. Compared to CRISPR/Cas9, AccuBase® does not cause DNA double-strand breaks, eliminating risks of DNA INDELs and chromosomal translocations. 
• Near-zero off-target effects. Compared to the previous generation of Cytosine Base Editors (CBEs), AccuBase®'s unique structural design releases deaminase activity only at the editing site, offering near-zero off-target effects and enhanced safety while maintaining high editing efficiency.
• GMP-grade and Research-Grade. Suitable for preclinical work, process development, and clinical research applications.
• Independent intellectual property and FTO available. It has completed independent intellectual property rights and holds foundational technology patents, with FTO (Freedom to Operate) designation. 

AccuBase® is an engineered DNA cytosine base editing protein that integrates a deaminase within the Cas9 nickase protein. When the AccuBase® protein forms a ribonucleoprotein (RNP) complex with single guide RNA (sgRNA), it remains in a non-editing state until it binds to the target DNA. Upon binding, a conformational change exposes the deaminase domain, enabling precise C-to-T editing within a 3-12 nucleotide window (with the first position being the farthest from the PAM sequence). In summary, AccuBase® significantly reduces random off-target risks while maintaining high-efficiency on-target editing.

The research-grade and GMP-grade products utilize the same bacterial source, raw materials, and production process, resulting in consistent protein activity. The differences are:

• Production environments: GMP-grade is produced in a cGMP environment, whereas research-grade is produced in non-GMP conditions.
• Quality control testing: GMP-grade AccuBase® undergoes comprehensive QC testing, including appearance, concentration, purity (2100), purity (SEC-HPLC), purity (RP-HPLC), endotoxin, residue DNase and RNase, host protein and DNA residue, sterility, and mycoplasma. Research-grade AccuBase® QC testing includes concentration, identification (Bis-Tris PAGE), purity (SEC-HPLC), and endotoxin. 
• Traceability documentation: GMP-grade has a full set of validation reports, stability study, COA, COO, animal-free statement, etc., and supports on-site audits. 

The molecular weight of AccuBase® is 210.14 kDa. The conversion is 10 mg/mL = 10 μg/μL = 47.59 μM; 1 μg = 4.759 pmol.

30 mM Tris, 300 mM NaCl, 0.1 mM EDTA, 1 mM DTT, 50% Glycerol, pH 8.0.

-80±10℃ for 3 years, avoid to repeated freeze-thaw.

• Correcting a single point mutation to restore the gene function
• Gene knockout by introducing a stop codon or altering splice sites, to silence a gene expression. 
• Multi-locus gene editing. It can also be combined with other gene editing tools.
• Electroporation or direct injection into cells, including adherent cells, suspension cells, embryonic cells (fish, mice, etc.), and plant embryos (gene gun method).

AccuBase® can not only achieve single-gene knockout but also simultaneously knock out 2, 3, or more genes.

The sgRNA scaffold used in AccuBase® is identical to that of spCas9. However, when designing sgRNAs for gene knockout applications, it is crucial to ensure that the target site includes editable cytosines (C) within the 3-12 nucleotide window. This positioning is essential to achieve efficient base editing while maintaining high specificity.

Using human TRAC gene as an example:

1. Download the gene sequence with annotated information and open it using SnapGene software.
2. Manually search the sequence information for the codon CAA, CAG, CGA, or TGG.
3. Check nearby for a suitable PAM sequence, using the NGG PAM sequence. Ensure that the edited C is within the editing window (3-12). Similar conditions apply to CAG and CGA. If it's TGG, check the position of the PAM on the antisense strand.

AccuBase® is a next-generation DNA cytosine base editing protein designed and developed by Base Therapeutics. It has completed independent intellectual property rights and holds foundational technology patents, with FTO (Freedom to Operate) available. Base Therapeutics is committed to an open, flexible, and sincere approach in its friendly negotiations with potential partners/clients.

Please find the usage details in the datasheet. For primary NK cells and primary T cells editing, in a 20μL electroporation system using Lonza's nucleofection device, the recommended amount of AccuBase® for electroporating 1E+06 cells is 80 pmol, with a 1:1 molar ratio to sgRNA. The recommended electroporation program is CM156.

For gene level analysis: Use Sanger sequencing followed by analysis with the online software EditR.

For protein level analysis: Use FACS flow cytometry (for cell membrane proteins).

You can order AccuBase® directly online via credit card or PO. Please send PO information to orders@kactusbio.us. To request a quote, please contact sales@kactusbio.us.

Research-grade: 100ug/vial, 200μg/vial, 500μL/vial, and 1mg/vial, at 10mg/mL concentration. 

GMP-grade: 1mg/vial at 10mg/mL concentration

Bulk sizes are available. Please contact sales@kactusbio.us.

AccuBase®, both research-grade and GMP-grade, is an off-the-shelf product. Catalog sizes ship
next-day in the contiguous US. For international customers, please expect up to a one-week lead time. For the lead time and price of bulk orders, please contact sales@kactusbio.us.

AccuBase® is a cytosine base editor engineered to convert C•G into T•A base pairs with high specificity. Unlike traditional base editors, AccuBase® integrates the deaminase domain within the Cas protein structure, minimizing exposure and reducing off-target activity.

AccuBase® is available in a GMP-grade format, produced under strict quality control standards. It uses animal-free components, is manufactured in line with regulatory guidelines, and comes with comprehensive batch documentation, making it suitable for CGT manufacturing workflows.

AccuBase® remains in a non-editing state until it binds to its target DNA. Its unique structural design conceals the deaminase, exposing it only when bound to the correct site—this significantly reduces off-target interactions with non-target DNA sequences.

AccuBase® enables precise C-to-T and G-to-A transitions, allowing for:

– Introduction of premature stop codons

– Splice site disruption

– Gene knockout and exon skipping applications

AccuBase® has been validated using GOTI to confirm minimal off-target activity. Flow cytometry shows knockout rates above 80 percent for PD1 and B2M, and 96 percent for TRAC in primary T cells.

No. Unlike traditional Cas9 nucleases, AccuBase® does not introduce INDELs or chromosomal translocations, offering a safer genome editing alternative with cleaner outcomes.

AccuBase® is produced in E. coli and supplied as a liquid formulation (10 mg/mL) in a stabilizing buffer. It should be stored at –80°C for long-term stability.

AccuBase® is available in both research-grade and GMP-grade formats:

– Research-grade: High-purity, validated for performance

– GMP-grade: Includes full regulatory documentation, QA release records, and enhanced process traceability.

QC metrics include endotoxin levels below 10 EU per mg, residual host DNA under 200 ng per mL, and greater than 80 percent purity by electrophoresis, HPLC, and SEC-HPLC.

Yes. Both research-grade and GMP-grade AccuBase® samples are available. You can also request batch records, QC reports, and other technical documentation to support your CGT research or manufacturing workflow.