Provided herein are expression cassettes for expressing a transgene in a liver cell, wherein the transgene encodes a PAH polypeptide. Also provided are methods to treat phenylketonuria (PKU) and/or to reduce levels of phenylalanine in an individual in need thereof. Further provided herein are vectors (e.g., rAAV vectors), viral particles, pharmaceutical compositions and kits for expressing a PAH polypeptide in an individual in need thereof.

Genetically engineered bacteria, pharmaceutical compositions thereof, and methods of modulating and treating diseases associated with hyperphenylalaninemia are disclosed.

Provided herein are phenylalanine-degrading enzyme variants for use in degrading phenylalanine and in treating phenylketonuria (PKU). More specifically, provided herein are phenylalanine-degrading enzyme variants that exhibit increased thermal stability and physicochemical resistance as measured by residual phenylalanine-degrading activity following challenge.

Genetically engineered bacteria, pharmaceutical compositions thereof, and methods of modulating and treating diseases associated with hyperphenylalaninemia are disclosed.

A method for producing a chain-shaped unsaturated carboxylic acid compound or a geometric isomer thereof, having at least two carbon-carbon double bonds, including the steps of: removing, from a chain-shaped unsaturated carboxylic acid compound or a geometric isomer thereof having an amino group and a carbon-carbon double bond at a terminus, that amino group, in the presence of phenylalanine ammonia lyase, and further forming a carbon-carbon double bond.

Aspects of the disclosure relate to aromatic amino acid ammonia lyases (ALs), phenylalanine ammonia lyases (PALs), and tyrosine ammonia lyase (TALs), including engineered enzymes, and their use in catalyzing chemical reactions.

Provided herein, among other things, is an engineered non-plant cell that produces a tropane alkaloid product, a precursor of a tropane alkaloid product, or a derivative of a tropane alkaloid product. A method for producing a tropane alkaloid, a precursor of a tropane alkaloid product, or a derivative of a tropane alkaloid product that makes use of the cell is also described.

Disclosed is a technique for constructing optogenetic amplifier and inverter circuits utilizing transcriptional activator/repressor pairs, in which expression of the transcriptional activator or repressor, respectively, is controlled by light-controlled transcription factors. This system is demonstrated utilizing the quinic acid regulon system from Neurospora crassa, or Q System, a transcriptional activator/repressor system. This is also demonstrated utilizing the galactose regulon from Saccharomyces cerevisiae, or GAL System. Such optogenetic amplifier circuits enable multi-phase microbial fermentations, in which different light schedules are applied in each phase to dynamically control different metabolic pathways for the production of proteins, fuels or chemicals. The orthogonal nature of the Q and GAL systems enable the co-expression of amplifier and inverter circuits to simultaneously amplify and invert the response of light-controlled transcriptional controls over different sets of genes in the same cell.

The present disclosure provides a variant of phenylalanine ammonia lyase (PAL), the phenylalanine ammonia lyase (PAL) being derived from Anabaena variabilis and comprises the amino acid sequence shown in SEQ ID NO: 1, wherein the variant comprises amino acid substitution C503S/C565L, so that the variant comprises the amino acid sequence shown in SEQ ID NO: 2; or amino acid substitution C503S/C565P, so that the variant comprises the amino acid sequence shown in SEQ ID NO: 3; or amino acid substitution C503L/C565P, so that the variant comprises the amino acid sequence shown in SEQ ID NO: 4. The present disclosure also provides a conjugate and a pharmaceutical composition comprising the variant, a polynucleotide encoding the variant, a bacterium comprising the variant, and a method for preparing the variant.