Provided are efficient catalyst of engineered enzymes and an economical enzymatic reaction solution to solve the problems in the current production process of L-tyrosine and its derivatives. The method of the invention has the advantages of high product concentration, mild reaction conditions, simple purification process, simple operation, environmental friendliness, and easy industrial scale-up. Thus, it has good industrial application prospects.

The present invention provides engineered tyrosine ammonia-lyase (TAL) polypeptides and compositions thereof. In some embodiments, the engineered TAL polypeptides have been optimized to provide enhanced catalytic activity while reducing sensitivity to proteolysis and increasing tolerance to acidic pH levels. The invention also provides methods for utilization of the compositions comprising the engineered TAL polypeptides for therapeutic and industrial purposes.

The present disclosure provides novel bacterial strains with altered expression or start codon modification of one or more RNA degradation/processing genes. The RNA degradation genes of the present disclosure are controlled by heterologous promoters. The present disclosure further describes methods for generating microbial strains comprising heterologous promoter sequences operably linked to RNA degradation/processing genes.

Provided herein are compounds of Formula A, methods for the preparation thereof, and uses thereof for treating or preventing bacterial infections.

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The present invention provides engineered tyrosine ammonia-lyase (TAL) polypeptides and compositions thereof. In some embodiments, the engineered TAL polypeptides have been optimized to provide enhanced catalytic activity while reducing sensitivity to proteolysis and increasing tolerance to acidic pH levels. The invention also provides methods for utilization of the compositions comprising the engineered TAL polypeptides for therapeutic and industrial purposes.

Systems, methods, and host cells utilizing a PopQC construct for enhancing product biosynthesis by exploitation of non-genetic cell-to-cell variation are disclosed. The PopQC construct includes at least a product-responsive biosensor and a selection gene.

Provided herein are biocatalysts and systems thereof for pterin-dependent enzymes and pathways and methods of making and using the same. Provided herein in some embodiments are biocatalysts having a pterin source and a pterin-dependent enzymatic pathway biologically coupled to the pterin source. Tetrahydrobiopterin (referred to herein as BH4 or BH 4) can be the pterin source. The BH4 can be synthesized by a tetrahydrobiopterin synthesis pathway. The tetrahydrobiopterin synthesis pathway can include a GTP cyclohydrase; a pyruvoyl tetrahydropterin synthase; a sepiapterin reductase, and/or any combination thereof. The biocatalyst can further contain a pterin-dependent enzymatic pathway. The pterin-dependent enzymatic pathway can be amino acid mono-oxygenase, phenylalanine hydroxylase, tryptophan hydroxylase, tyrosine hydroxylase, nitric oxide synthase, alkylglycerol monooxygenase, and/or any combination thereof.

Host cells that are engineered to produce benzylisoquinoline alkaloid (BIAs) precursors, such as norcoclaurine (NC) and norlaudanosoline (NL), are provided. The host cells may have one or more engineered modifications selected from: a feedback inhibition alleviating mutation in a enzyme gene; a transcriptional modulation modification of a biosynthetic enzyme gene, an inactivating mutation in an enzyme; and a heterologous coding sequence. Also provided are methods of producing a BIA of interest or a precursor thereof using the host cells and compositions, e.g., kits, systems etc., that find use in methods of the invention.

The present disclosure provides a variant tyrosine hydroxylase that provides for increased production of L-DOPA in a host cell that expresses the tyrosine hydroxylase. The present disclosure provides nucleic acids encoding the variant tyrosine hydroxylase, and host cells genetically modified with the nucleic acids. The present disclosure provides methods of making L-DOPA in a host cell. The present disclosure provides methods of making a benzylisoquinoline alkaloid (BIA), or a BIA precursor. The present disclosure provides methods of detecting L-DOPA level in a cell. The present disclosure provides methods of identifying tyrosine hydroxylase variants that provide for increased L-DOPA production; and methods of identifying gene products that provide for increased tyrosine production.

The present disclosure relates to an L-tyrosine-producing microorganism, comprising a trp operon regulatory region and a gene encoding prephenate dehydratase operably linked thereto, and a method for producing L-tyrosine using the microorganism.