Biology subjects

Kurnia, K.

Publications and source records attributed to Kurnia, K..

3 recordsLinked to original sources

bioRxiv2026

Dual-Chassis Strategy for Bridging Adaptive Evolution and Rational Design for Synthetic Biology

Genome streamlining and pathway refactoring are powerful strategies for constructing controllable microbial chassis for both fundamental studies and applications. While rational design benefits from reduced genetic complexity, adaptive laboratory evolution (ALE) thrives on metabolic redundancy, creating a mismatch between optimal hosts for design and evolution. Here, we introduce a dual chassis framework (DUET) in which rational pathway construction and adaptive evolution are first carried out in an evolution-competent host, and the resulting optimized designs are subsequently transferred into a genetically stable chassis for deployment. Using the naturally evolvable bacterium Acinetobacter baylyi ADP1 and its genome-stabilized derivative (ISx), we applied this framework to the {beta}-ketoadipate pathway, a central hub for aromatic compound catabolism. We first streamlined the native network by deleting individual pathway branches and then engineered a minimal synthetic route that merges protocatechuate and catechol metabolism. Subsequent ALE enabled efficient growth through this synthetic pathway, and reverse-engineering identified key adaptive mutations underlying functional recovery. Both the synthetic pathway and the mutations were transferred unchanged into ISx, where robust growth was maintained without further adaptation. These results demonstrate that DUET enables portable, host-independent deployment of rational metabolic streamlining combined with evolution, providing a generalizable strategy for building reduced yet robust microbial platforms. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=78 SRC="FIGDIR/small/729570v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@19ba68forg.highwire.dtl.DTLVardef@1d40eb4org.highwire.dtl.DTLVardef@1115597org.highwire.dtl.DTLVardef@10a50f4_HPS_FORMAT_FIGEXP M_FIG C_FIG

synthetic biology↗

bioRxiv2024

Shikimate pathway-Dependent Catabolism:enabling near-to-maximum production yield of aromatics

Catabolism is a complex network of tightly regulated metabolic reactions that provides energy and carbon to fuel anabolism in all living organisms. Rewiring catabolism is essential for harnessing industrial biotechnology but remains a substantial metabolic engineering challenge due to its high genetic stability and tight regulation acquired through evolution. In this study, by combining metabolic modeling, rational engineering, and adaptive laboratory evolution, we fundamentally redesigned bacterial catabolism. We created a new-to-nature shikimate pathway-dependent catabolism (SDC) in Pseudomonas putida by reprogramming the shikimate pathway as the primary catabolic route. SDC supports growth by supplying the glycerol catabolic end-product pyruvate, enabling superior production of shikimate pathway-derived molecules. Through SDC, aromatics production reached over 89% of the pathways maximum theoretical yield, setting a new benchmark for their microbial synthesis. Our study successfully repurposed an anabolic pathway for catabolism, exemplifying the high metabolic plasticity of microbes and providing a bacterial chassis for the efficient production of high-added value compounds.

synthetic biology↗

bioRxiv2024

Metabolic engineering of Acinetobacter baylyi ADP1 for naringenin production

Naringenin, a flavanone and a precursor for a variety of flavonoids, has potential applications in the health and pharmaceutical sectors. The biological production of naringenin using genetically engineered microbes is considered as a promising strategy. The naringenin synthesis pathway involving chalcone synthase (CHS) and chalcone isomerase (CHI) relies on the efficient supply of key substrates, malonyl-CoA and coumaroyl-CoA. In this research, we utilized a soil bacterium, Acinetobacter baylyi ADP1, which exhibits several characteristics that make it a suitable candidate for naringenin biosynthesis; the strain naturally tolerates and can uptake and metabolize coumarate, a primary compound in alkaline-pretreated lignin and a precursor for naringenin production. A. baylyi ADP1 also produces intracellular lipids, such as wax esters, thereby being able to provide an excess of malonyl-CoA for naringenin biosynthesis. Moreover, the genomic engineering of this strain is notably straightforward. In the course of the construction of a naringenin-producing strain, the coumarate catabolism was eliminated by a single gene knockout ({Delta}hcaA) and various combinations of plant-derived CHS and CHI were evaluated. The best performance was obtained by a novel combination of genes encoding for a CHS from Hypericum androsaemum and a CHI from Medicago sativa, that enabled the production of 18 mg/L naringenin in batch cultivations from coumarate. Furthermore, the implementation of a fed-batch system led to a significant 3.7-fold increase (66 mg/L) in naringenin production. These findings underscore the potential of A. baylyi ADP1 as a host for naringenin biosynthesis as well as advancement of lignin-based bioproduction.

bioengineering↗