Search bioRxiv⌕ Search

bioRxiv · 10.1101/2022.03.25.485857

Unleashing the Potential of Noncanonical Amino Acid Biosynthesis for Creation of Cells with Site-Specific Tyrosine Sulfation

Abstract

Incorporation of noncanonical amino acids (ncAAs) into proteins holds great promise for modulating the structure and function of those proteins and for influencing evolutionary dynamics in organisms. Despite significant progress in improving the efficiency of translational machinery needed for incorporating ncAAs, exogenous feeding of high concentrations of chemically-synthesized ncAAs, especially in the case of polar ncAAs, is required to ensure adequate intracellular ncAA levels. Here, we report the creation of autonomous cells, both prokaryotic and eukaryotic, with the ability to biosynthesize and genetically encode sulfotyrosine (sTyr), an important protein post-translational modification with low membrane permeability. We discovered the first enzyme catalyzing tyrosine sulfation, sulfotransferase 1C1 from Nipponia nippon (NnSULT1C1), using a sequence similarity network (SSN). The unique specificity of NnSULT1C1 for tyrosine has been systematically explored using both bioinformatics and computational methods. This NnSULT1C1 was introduced into both bacterial and mammalian cells so as to yield organisms capable of biosynthesizing high levels of intracellular sTyr. These engineered cells produced site-specifically sulfated proteins at a higher yield than cells fed exogenously even with the highest level of sTyr reported in literature. We have used these autonomous cells to prepare highly potent thrombin inhibitors with site-specific sulfation. By enhancing ncAA incorporation efficiency, this added ability of cells to biosynthesize ncAAs and genetically incorporate them into proteins greatly extends the utility of genetic code expansion methods. TOC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=188 SRC="FIGDIR/small/485857v1_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@2c3b08org.highwire.dtl.DTLVardef@1d7a914org.highwire.dtl.DTLVardef@19d9f91org.highwire.dtl.DTLVardef@156ee8c_HPS_FORMAT_FIGEXP M_FIG C_FIG

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Chen, Y., Jin, S., Zhang, M., Wu, K.-l., Chang, A., Wang, S., Tian, Z., Wolynes, P. G., Xiao, H.. 2022-03-26. Unleashing the Potential of Noncanonical Amino Acid Biosynthesis for Creation of Cells with Site-Specific Tyrosine Sulfation. https://doi.org/10.1101/2022.03.25.485857

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Coupled enzyme discovery, evolution and synthetic yeast chassis adaptation for microbial biopolymer valorisation

The valorisation of biological polymers requires microbial systems that can both access recalcitrant substrates and convert the resulting carbon into useful products. Although microbial genome and metagenome resources provide an expanding reservoir of candidate depolymerizing and modifying enzymes, most discovery workflows remain disconnected from enzyme optimisation and host adaptation. Here we present a coupled sequence-based enzyme discovery, enzyme evolution and synthetic yeast chassis adaptation strategy for microbial biopolymer valorisation. Focusing on laccases for the depolymerisation of lignin as a proof of concept, we combine sequence data mining for enzyme discovery, modular yeast surface display for functional screening, directed evolution for enzyme optimisation and synthetic yeast genome diversification for chassis improvement. In our study, surface display enabled functional benchmarking and recovery of improved laccase variants and synthetic-genome-enabled diversification provided a route to explore host configurations that influence display and enzyme performance. By integrating enzyme-level and chassis-level optimisation, this framework addresses a central bottleneck in converting microbial biodiversity by computational sequence repository mining into deployable biomanufacturing systems. Our results establish laccases as tractable entry points for oxidative biopolymer conversion and provide a generalizable platform for engineering yeast systems for sustainable carbon valorisation.

synthetic biology↗

Multichromatic Dynamic Control of Multi-Membered Microbial Consortia Compositions for Chemical Production

Engineered microbial consortia offer a promising strategy for chemical production by distributing specialized functions among microbial strains, reducing metabolic burden, facilitating modular pathway optimization, reducing toxicity, and increasing strain stability. However, differences in growth rates can destabilize population composition, compromising productivity and limiting their applicability. Here, we developed a multichromatic optogenetic Toxin-Antitoxin (optogeneticTA) platform for dynamic control of Escherichia coli consortia of up to four members using blue, red, and near-infrared light and darkness. By varying light intensities or pulses, we precisely program and dynamically modulate the population composition of two-, three-, and four-membered consortia. We further developed a modular mathematical framework that captures and predicts population dynamics of these optogenetically controlled co-cultures. Applying dynamic control to a two-membered engineered consortium increased phenol production by ~69% relative to unregulated consortia. These results establish a programmable platform for stabilizing and dynamically optimizing microbial consortia, with potential applications across microbial biomanufacturing.

synthetic biology↗

Reassessing the contribution of the histone H3 tail to KRAB-DNMT3L-mediated epigenetic silencing

Neumann et al. introduced CHARM, a compact epigenetic silencer in which a histone H3 tail fused to DNMT3L was proposed to recruit and stimulate endogenous DNMT3A, enabling durable gene repression without a fused DNMT3A catalytic domain. Here, we evaluated the contribution of the H3 tail in independent reporter and endogenous-gene contexts. In an SNRPN reporter system, a KRAB-DNMT3L-dCas9 construct lacking the H3 tail displayed silencing kinetics comparable to CRISPRcharm Kv2, and mutating the critical H3K4 residue to alanine in CRISPRcharm Kv2 did not compromise this silencing. Similarly, after transient delivery of editor mRNAs to HEK293T cells, CRISPRcharm Kv2 did not consistently outperform the corresponding H3-tail-free construct at three endogenous loci, and mutating the critical H3K4 residue to alanine in CRISPRcharm Kv2 did not compromise this activity. These observations suggest that the engineered H3 tail does not confer a general functional advantage within the KRAB-DNMT3L-dCas9 architecture under the conditions tested.

synthetic biology↗