Hello everyone, this issue brings you Nature Communications, a sub-publication under Nature Group, specializing in publishing high-quality research papers in various fields such as biology, physics and chemistry. The impact factor in 2021 is 17.694.

Hello everyone, this issue brings you Nature Communications, a sub-public of Nature Group, specializes in publishing high-quality research papers in various fields such as biology, physics and chemistry. The impact factor in 2021 is 17.694.

1

The evolutionary advantage of an aromatic clamp in plant family 3 glycoside exo-hydrolases

plant family of glycoside exohydrolases 3 in barley In β-D-glucan glucosidase, a family of glycoside hydrolase 3 (GH3) enzymes, Trp286/Trp434 clamps ensure β-D-glucosidoside binding, which is the basis for substrate hydrolysis during plant growth and development. The authors use mutation, high-resolution X-ray crystallography, and multi-scale molecular modeling methods to study the binding and conformational behavior of isomerized β-D-glucosides during substrate product-assisted processing catalysis operated in GH3 hydrolase. Enzyme kinetics suggest that W434H mutants retain extensive specificity, while W434A is a strict (1,3)-β-D-glucosidase. Studies on nanoscale reactant movements have shown that the ability to sustain synthesis is sensitive to mutation-specific changes in tryptophan pincers. Although wild-type and W434H use side cavity for glucose replacement and allow (1,3) linked hydrolysates to slide through catalytic sites without dissociation, which is consistent with their high hydrolysis rates and their high hydrolysis rates, W434A does not employ continuous catalysis. Systematic genomic analysis of GH3 hydrolase reveals the evolutionary advantages of tryptophan pincers, which have broad specificity, high catalytic efficiency and processing capabilities.

2

Screening microbially produced Δ⁹-tetrahydrocannabinol

using a yeast biosensor workflow

Screening microbial production Δ⁹-tetrahydrocannabinol

Microorganisms Produced cannabinoids are expected to provide a consistent, cheap and more sustainable supply to important therapeutic molecules. However, expanding production to compete with traditional plant sources is a challenge. Screening and identification of high yield mutant strains is a bottleneck in this work. In this study, the authors proposed a yeast-based biosensor to detect Δ⁹-tetrahydrocannabinol (THC) produced by microorganisms to increase throughput and reduce screening costs. The authors transplanted five human cannabinoid G protein-coupled receptors (GPCRs) into yeast, showing that the cannabinoid type 2 receptor CB2R can be coupled to the yeast pheromone response pathway and report the concentrations of various cannabinoids over a wide range of dynamics and operating ranges. The authors demonstrate that cannabinoid biosensors can detect THC in microbial cell cultures and use it as a tool to measure the relative yield of the Δ⁹-tetrahydrocannabinolate synthase (THCAS) mutant library.

3

Biosynchosis of plant hemosti dencichine in Escherichia coli

Biosynthesis of plant trichodin in Escherichia coli

Biosynthesis of plant trichodin in Escherichia coli

Trichodin is a plant-derived natural product with a variety of pharmacological effects. At present, its natural biosynthesis pathway is still unclear, posing challenges to its heterologous biosynthesis. In this study, the author designed an artificial pathway through the reverse transcription biosynthesis method and achieved the de novo production of trichodin. First, the biosynthesis of two direct precursors L-2, 3-diaminopropionic acid and oxalyl Coenzyme A was achieved by screening and integrating microbial enzymes. Secondly, by introducing 28 synonymous rare codons into the codon optimization gene to slow down its translation speed, the solubility of taxacin synthase, which is the last and only plant-derived pathway enzyme, was significantly improved. Finally, the metabolic network was systematically designed to direct carbon flux to trichondria production, and finally titer reached 1.29 g L-1. This work lays the foundation for the sustainable production of trichodin and represents an example of how synthetic biology can be used to produce unnatural pathways to produce desired molecules.

4

2

Enzymatic synthesis of benzylisoquinoline alkaloids using a parallel cascade strategy and tyrosinase variants synthesis of benzylisoquinoline alkaloids using a parallel cascade strategy and tyrosinase variants enzymatic synthesis of benzylisoquinoline alkaloids

benzylisoquinoline alkaloids derived drugs are widely used in modern medicine. Recent studies on the production of benzylisoquinoline microbials have highlighted the key biosynthesis of these natural products. Natural benzyl isoquinoline has less route exploration, especially with more challenging halogenated compounds. In this study, the authors demonstrated the use of tyrosinase , tyrosine decarboxylase, transaminase and noraminine synthase, which are combined in parallel cascade designs to produce a high enantiomer excess of halobenzyl isoquinoline alkaloids. It is worth noting that mutagenesis studies have been applied to the production of tyrosinase mutants, thereby increasing the acceptance of halotyrosine use in the developed biocatalytic cascades.

5

Kinetic compartmentalization by unnatural reaction for itaconate production

Kinetic partitioning using unnatural reactions to produce itaconic acid

Physical division of metabolism using membrane organelles in eukaryotes facilitates chemical biosynthesis to ensure the availability of substrates in competitive metabolic reactions. The bacterial host lacks such an membrane system, , which is one of the main limitations of efficient metabolic engineering. In this study, the authors used kinetic partitioning to introduce non-natural enzymatic reactions through engineered enzymes as an alternative strategy to obtain substrates from competitive reactions through kinetic separation of metabolic pathways. As a proof of concept, the authors dynamically isolated the itaconic acid synthesis pathway from the tricarboxylic acid cycle of E. coli, which is naturally separated by the mitochondrial membrane of Aspergillus turperus. Specifically, 2-methyl citrate dehydrase has been engineered to alternately catalyze citrate and kinetic-fixed cisconic acid, thereby efficient production using a high-throughput screening system. Kinetic partitioning can significantly increase the yield of itaconic acid, and its strategy has the potential for widespread application.

6

2

Elucidation of diverse desaturation pathways in the formation

of vinyl isonitrile and isocyanoacrylate

Interpretation of different desaturation pathways in the formation of vinyl isonitrile and isocyanoacrylate

Ferro and 2-oxoglutarate dependency (Fe/2OG) enzymes use two different types of desaturation to construct the vinyl isonitrile and isocyanoacrylate moieties found in natural products containing isonitrile. The structure of proteins bound to substrates reveals a reasonable strategy to influence desaturation and implies substrate confounding for these enzymes. The analogs were synthesized and used as mechanical probes to verify structural observations. Unlike the previously proposed intermediates by hydroxylation, a possible carbo-positive ion is used to trigger the C=C bond installation. These Fe/2OG enzymes can also adapt to analogs with opposite chirality and different functional groups, including isonitrile-(D)- tyrosine , N-formyl tyrosine and pantothenic acid, while maintaining reaction selectivity.