Modified Corynebacterium glutamicum for Polyketide Production

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Corynebacterium glutamicum's growth is inhibited by propionate due to accumulation of propionyl-CoA and methylmalonyl-CoA, which hinders polyketide production, and existing methods lack effective strategies to selectively enhance polyketide synthase activity.

Innovation Solution

Genetically modify Corynebacterium glutamicum to knock out genes involved in propionyl-CoA and methylmalonyl-CoA catabolism and introduce methylmalonyl-CoA-dependent polyketide synthases, allowing the bacteria to utilize these CoA derivatives for polyketide production, thereby overcoming growth inhibition and increasing production efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If propionate is added to increase methylmalonyl-CoA concentration for polyketide production, then polyketide production is improved, but growth inhibition occurs due to accumulation of propionyl-CoA and methylmalonyl-CoA

Engineering Contradiction:

Improvepolyketide productionVSAvoidgrowth rate

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent converts the harmful accumulation of propionyl-CoA and methylmalonyl-CoA (which causes growth inhibition) into a beneficial effect by introducing methylmalonyl-CoA-dependent polyketide synthases that consume these accumulated intermediates to produce polyketides. The harmful metabolic bottleneck becomes the source of high-titer polyketide production.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent changes the metabolic parameters by knocking out genes involved in propionyl-CoA and methylmalonyl-CoA catabolism (such as mcmAB and prp genes), thereby preventing the degradation of these intermediates and forcing their accumulation to be redirected toward polyketide synthesis through the introduced PKS pathways.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If genes for propionyl-CoA and methylmalonyl-CoA catabolism are knocked out to prevent accumulation, then growth inhibition is reduced, but polyketide production is hindered due to insufficient substrate availability

Engineering Contradiction:

Improvegrowth rateVSAvoidpolyketide production

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

By knocking out catabolic genes, the patent prevents the harmful degradation of propionyl-CoA and methylmalonyl-CoA, causing these intermediates to accumulate. This accumulation is then beneficially utilized by the introduced methylmalonyl-CoA-dependent PKS enzymes as substrates for polyketide synthesis.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent introduces heterologous methylmalonyl-CoA-dependent polyketide synthase genes (such as gcs from Streptomyces coelicolor) as intermediary enzymes that bridge the gap between the accumulated CoA derivatives and polyketide production, enabling the conversion of metabolic intermediates into valuable polyketide products.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Productivity

If Streptomyces is used as host for polyketide production with native propionate utilization pathway, then polyketide production is achieved, but slow growth rate and complex life cycles reduce productivity

Engineering Contradiction:

Improvepolyketide productionVSAvoidgrowth rate

Core Design Contradiction:

ProductivityVSSpeed

Solution Approach 1:

The patent transfers the polyketide synthesis capability to Corynebacterium glutamicum, a host with faster growth rate and simpler lifecycle. The introduced PKS pathway provides universal polyketide production capability in this improved host, replacing the need for Slow-growing Streptomyces while maintaining production capability.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent changes the host organism parameters from Streptomyces (slow growth, complex lifecycle) to Corynebacterium glutamicum (fast growth, simple lifecycle), while simultaneously adjusting the metabolic pathway parameters by knocking out specific genes and introducing heterologous PKS genes to achieve both fast growth and high polyketide production.

Inventive Principle:

Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The modified host cells exhibit improved polyketide production and growth rates, enabling the selection of strains with enhanced productivity through directed evolution and propionate-induced selective pressure, significantly increasing germicidin titer and reducing growth inhibition in propionate media.

Implementation Method 1

methylmalonyl-CoA-dependent polyketide synthase (PKS)

Methodology Applied

Scientific EffectEnzymatic catalysis: Enzyme

Implementation Method 2

propionate carboxylation pathway also results in less carbon loss to CO2

Methodology Applied

Scientific EffectCarboxylation:

Data Source

PatentUS20240425891A1Host cells and methods for improved polyketide production using methylmalonyl-CoA-dependent polyketide synthase (PKS)

Publication Date: 2024.12.26 RGT UNIV OF CALIFORNIA

AI summary

The present invention provides for a genetically modified host cell reduced for expression of one of more endogenous enzyme(s) which enable the catabolism of propionyl-CoA and/or methylmalonyl-CoA, and comprising a methylmalonyl-CoA-dependent polyketide synthase (PKS).