Valine Bioproduction Engineering Service

Valine (Val) is a crucial branched-chain amino acid (BCAA) used extensively as an additive in the animal feed industry and in human nutritional supplements. Industrial production using microbial fermentation, often relying on Corynebacterium glutamicum, is limited by a low acid production rate in fermentation due to strict metabolic regulation and feedback inhibition. Furthermore, the inherent hydrophobicity of the amino acid and the characteristics of the host cell wall often lead to insufficient extraction yield from the fermentation broth, increasing downstream costs. Overcoming these twin challenges is key to making biosynthetic Valine cost-competitive.

CD Biosynsis offers a synthetic biology service focused on engineering Corynebacterium glutamicum for high-titer Valine production. Our core strategy involves modification of valine synthase in Corynebacterium glutamicum . Valine synthesis is tightly regulated by feedback inhibition of Acetolactate Synthase (IlvN/D/E operon), the key enzyme in the BCAA pathway. We focus on modifying the regulatory subunit (IlvN) to create a feedback-resistant variant , ensuring the pathway remains active even at high internal Valine concentrations. This is coupled with optimization of cell membrane permeability . We employ targeted genetic engineering (e.g., modifying genes related to cell wall synthesis or introducing specific transporter proteins like Valine efflux pumps) to enhance the rate of Valine excretion from the cell into the fermentation medium. This dual approach not only boosts the intrinsic production rate (Valine Synthase Modification) but also ensures efficient product release into the broth, mitigating toxicity and significantly improving the overall extraction yield and downstream processing efficiency. This creates a scalable, high-yield, and cost-effective L-Valine manufacturing platform.

Pain Points

Achieving cost-effective, high-yield Valine production faces these key challenges:

• Low Acid Production Rate in Fermentation: The BCAA pathway's first committed step (Acetolactate Synthase) is strongly subject to feedback inhibition by Valine and Leucine , stalling production at high internal concentrations.
• Insufficient Extraction Yield: Valine is neutral and hydrophobic, and the thick cell wall of C. glutamicum limits the natural efflux of the product, necessitating costly cell disruption or complex extraction methods.
• Metabolic Leakage: Valine shares an intermediate (a-ketoisovalerate) with Leucine and Isoleucine synthesis, leading to carbon flux diversion to other BCAAs.
• Internal Product Toxicity: As Valine accumulates inside the cell due to poor efflux, it becomes toxic to the host organism , further reducing cell growth and production rate.

A successful solution must remove metabolic feedback control and actively promote product secretion.

Solutions

CD Biosynsis utilizes advanced metabolic engineering to optimize Valine production in C. glutamicum:

Modification of Valine Synthase in C. glutamicum

           

We mutate the regulatory subunit (IlvN) of Acetolactate Synthase to render the enzyme feedback-resistant to Valine and Leucine.

Optimization of Cell Membrane Permeability

We overexpress heterologous or native amino acid efflux pump genes (e.g., BCAA transporters) to actively push Valine out of the cell.

Competing Pathway Blockade

We delete IlvD or IlvC variants that lead to Leucine and Isoleucine synthesis, ensuring maximum carbon flux toward Valine.

Precursor Supply Enhancement

We optimize the upstream Pyruvate dehydrogenase complex and TCA cycle flux to increase the supply of the Pyruvate precursor.

This systematic approach ensures a high internal production rate and highly efficient external secretion, maximizing final yield.

Advantages

Our Valine engineering service is dedicated to pursuing the following production goals:

High Fermentation Titer

Removal of feedback inhibition ensures a continuous, fast acid production rate even at high concentrations, solving the low-yield issue.

Improved Extraction Yield

Active efflux pumps increase product secretion, reducing downstream purification costs and making the process economically competitive. [Image of Cost Reduction Icon]

L-Valine Purity Guarantee Icon

Biosynthesis ensures the production of the biologically active L-isomer required for feed and food applications.

C. glutamicum GRAS Host Icon

Uses a generally recognized as safe (GRAS) host for safe and regulatory-compliant food/feed production.

Reduced Product Toxicity

Active Valine efflux prevents internal accumulation, improving cell viability and overall productivity.

We provide a sustainable, high-performance, and economically optimized L-Valine manufacturing solution.

Process

Our Valine strain engineering service follows a rigorous, multi-stage research workflow:

• Acetolactate Synthase Mutagenesis: Introduce site-directed mutations into the IlvN regulatory subunit to remove feedback inhibition.
• Efflux Pump Integration: Identify and overexpress a Valine efflux pump (e.g., BrnF) to facilitate rapid product secretion into the medium.
• Competing Pathway Blockade: Delete IlvA (Threonine deaminase) and downregulate Leucine/Isoleucine branches to direct flux toward Valine.
• Precursor Supply Optimization: Engineer the upstream Pyruvate metabolism (e.g., Pyruvate carboxylase) to increase Pyruvate availability for Valine synthesis.
• Functional and Titer Assays: Validate the engineered strain in fed-batch culture, measuring the final Valine concentration and secretion rate .
• Result Report Output: Compile a detailed Experimental Report including gene modification data, enzyme characterization, and fermentation metrics (final titer, yield, and membrane permeability index) , supporting industrial scale-up.

Technical communication is maintained throughout the process, focusing on timely feedback regarding yield and secretion efficiency.

Explore the potential for a high-performance Valine supply. CD Biosynsis provides customized strain and pathway engineering solutions:

• Detailed Feedback Resistance and Secretion Efficiency Report , demonstrating the functional change in IlvN}^{mut and the efflux pump's impact on yield.
• Consultation on optimized pH and osmotic pressure conditions for enhanced Valine secretion in the fermenter.
• Experimental reports include complete raw data on Valine productivity (g/L/h) and carbon yield (g/g glucose) , essential for cost-reduction analysis.