Glycine Bioproduction Engineering Service

Glycine is the simplest amino acid and is widely used in the food industry, pharmaceuticals, and as an industrial raw material. Traditional chemical synthesis often results in insufficient purity in chemical synthesis , requiring costly and complex downstream purification to remove hazardous by-products. While microbial biosynthesis is a cleaner alternative, it is challenged by a low conversion rate in biosynthesis because the Glycine synthesis pathway is tightly regulated and shares precursors with essential pathways (e.g., Serine and C1 metabolism), leading to low final yield. Optimization requires fine-tuning the metabolic switch.

CD Biosynsis offers a synthetic biology service focused on high-conversion Glycine production in Escherichia coli. Our core strategy involves modification of glycine synthase in Escherichia coli . The primary Glycine synthesis route from Serine is via Serine Hydroxymethyltransferase (SHMT, GlyA), and the degradation route is via the Glycine Cleavage System (GCS), an irreversible Glycine Synthase in reverse. We specifically downregulate the GCS complex (Glycine Synthase) and overexpress a deregulated GlyA to drive the net flux towards Glycine accumulation. This is coupled with relief of metabolic inhibition . We identify and genetically modify key regulatory sites that are inhibited by accumulated Glycine or its co-factors (e.g., NADH, folate derivatives) in the SHMT or upstream Serine pathway. We also ensure a sufficient supply of Serine by optimizing the glycolysis flux. This integrated approach aims to deliver high-titer, high-purity Glycine through a clean, bio-based route, achieving superior product quality compared to chemical methods.

Pain Points

Developing a cost-effective, high-quality Glycine production route faces these key limitations:

• Insufficient Purity in Chemical Synthesis: Chemical routes often use toxic intermediates (e.g., chloroacetic acid) and result in numerous side-reaction by-products , complicating purification to pharmaceutical grade.
• Low Conversion Rate in Biosynthesis: The primary synthesis enzyme (SHMT) is highly regulated and inhibited by Glycine. Furthermore, the Glycine Cleavage System (GCS) acts as a strong sink, readily degrading the product.
• Serine Precursor Bottleneck: The supply of Serine (the direct precursor) from glycolysis is tightly controlled, leading to a rate-limiting step for Glycine production.
• C1 Metabolism Competition: Glycine is tightly linked to one-carbon (C1) metabolism. Flux is constantly diverted to essential cellular components (e.g., purines and thymidylate), causing carbon leakage .

A successful solution must drive the flux from Serine to Glycine while eliminating the Glycine degradation route.

Solutions

CD Biosynsis utilizes advanced metabolic engineering to optimize Glycine production in E. coli:

Modification of Glycine Synthase in E. coli

           

We delete or significantly downregulate the Glycine Cleavage System (GCS) , the key degradation pathway, effectively turning off the Glycine Synthase function.

Relief of Metabolic Inhibition

We apply site-directed mutagenesis to Serine Hydroxymethyltransferase (GlyA) to render it resistant to feedback inhibition by high intracellular Glycine levels.

Serine Pathway Flux Reinforcement

We overexpress key enzymes (e.g., SerA) in the pathway from 3-Phosphoglycerate to Serine to ensure a large and sustained supply of the direct precursor.

C1 Metabolism Bypass/Blockade

We downregulate or knock out competing pathways (e.g., purine synthesis) that consume the C1 units linked to Glycine synthesis, maximizing the final Glycine yield.

This systematic approach addresses both the rate of synthesis and the rate of degradation to maximize Glycine accumulation.

Advantages

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

Ultra-High Purity Product

Biosynthesis avoids the hazardous, difficult-to-separate by-products of chemical synthesis, leading to pharmaceutical-grade Glycine .

Elimination of Product Loss

Knockout of the Glycine Cleavage System (GCS) prevents the primary route of Glycine degradation, solving the low conversion rate issue. [Image of Cost Reduction Icon]

High Fermentation Titer

Enhanced precursor supply (Serine) and inhibition-resistant enzymes drive a higher accumulation of Glycine in the broth.

Reduced Downstream Purification Cost

The cleaner broth produced by biosynthesis simplifies crystallization and purification , significantly reducing operational expenses.

Sustainable Production Route

Fermentation utilizes renewable sugars as feedstock, offering an eco-friendly alternative to petroleum-based chemical methods.

We provide a competitive, high-quality, and green manufacturing platform for Glycine.

Process

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

• Degradation Pathway Blockade: Use precise gene editing (e.g., CRISPR) to delete the entire Glycine Cleavage System (GCS) operon (glyH, glyT, glyA, glyB in reverse).
• Serine Precursor Optimization: Overexpress the Serine biosynthesis pathway (SerA, SerB, SerC) to maximize the supply of the direct precursor.
• Enzyme Inhibition Relief: Perform site-directed mutagenesis on Serine Hydroxymethyltransferase (GlyA) to create a variant with reduced Glycine feedback sensitivity.
• Metabolic Flow Control: Use genetic tools to downregulate the C1 consuming pathways (purine and thymidylate synthesis) to prevent carbon leakage.
• Fermentation Performance Validation: Test the final engineered strain in fed-batch fermentation to assess Glycine titer, yield, and by-product profile .
• Result Report Output: Compile a detailed Experimental Report including gene modification data, enzyme characterization, and fermentation metrics (titer, yield, and purity) , supporting industrial scale-up.

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

Explore the potential for a high-purity, cost-effective Glycine supply. CD Biosynsis provides customized strain and pathway engineering solutions:

• Detailed Yield and Purity Analysis Report , demonstrating the elimination of degradation and by-products.
• Consultation on optimized pH and nutrient feeding strategies to maintain SHMT activity and minimize stress.
• Experimental reports include complete raw data on carbon yield (g Glycine/g glucose) and final product purity (%) , essential for food and pharmaceutical applications.