An alkaline protease mutant, and a gene, engineered strain, a preparation method and application thereof are provided. The method comprises the following steps of extracting genome DNA of Bacillus clausii, performing PCR amplification to obtain a wild-type alkaline protease gene sequence, mutating the wild-type alkaline protease gene obtained by the amplification through an error-prone PCR, performing high-throughput screening to obtain a plurality of highly active alkaline protease genes, performing DNA shuffling on the highly active alkaline protease genes, and performing screening to obtain eight alkaline protease mutant genes with higher activity.

Compositions and methods are provided for modulating growth of a genetically modified bacterial cell present in a human organ, for modulating growth of a genetically modified bacterial cell in an organ (e.g., gut), for displacing at least a portion of a population of bacterial cells in an organ, and for facilitating gut colonization by a genetically modified bacterial cell. Also provided are genetically modified bacterial cells, e.g., cells that include a heterologous carbohydrate-utilization gene or gene set that provides for the ability to utilize as a carbon source a rare carbohydrate of interest that is utilized as a carbon source by less than 50% of bacterial cells present in a human microbiome.

The present disclosure relates to a protein variant having a tryptophan-exporting activity, an L-tryptophan-producing microorganism expressing the protein variant, and a method for producing L-tryptophan using the microorganism.

Methods of producing fatty acid esters, such as fatty acid ethyl esters, from genetically engineered microorganisms are described.

The present disclosure relates to a novel method of producing vanillin and/or derivatives thereof by applying improved biocatalysts. Also provided herein are expression systems for preparing said improved biocatalysts. Moreover provided herewith are novel enzyme mutants, corresponding coding sequences and vectors applicable in the biochemical production of vanillin. The present disclosure further provides recombinant host cells or organisms genetically modified for improved functional expression of biocatalysts, as well as recombinant host cells or organisms useful to produce vanillin.

The present invention relates to a Plasmid Addiction System for the stabilization of expression plasmids encoding proteins of interest. The invention uses a succinate cycle optimization to ensure the expression of plasmid(s) of interest. By ensuring that plasmids of interest contain genes necessary in the succinate cycle, the system ensures that the passage of the plasmid to daughters and therefore improves the efficiency of production and expression of genes and/or products of interest.

The present invention refers to lambda integrases comprising at least one amino acid mutation at positions 43, 319 and 336 of the lambda integrase as set forth in SEQ ID NO: 1. The invention further refers to nucleic acid molecules comprising the nucleotide sequence encoding the mutant lambda integrase and to host cells containing these nucleic acid molecules. The invention also refers to methods of recombining a nucleic acid of interest into a target nucleic acid in the presence of the mutant lambda integrase and sequence specific recombination kits.

The present invention provides a DNA polymerase including the sequence of SEQ ID NO. 1 or a sequence which is at least 70% identical thereto, but wherein the aspartic acid residue at position 18 of SEQ ID NO. 1, or the equivalent aspartic acid residue in other sequences, has been replaced by a non-negatively charged amino acid residue. It further provides DNA polymerases comprising the amino acid sequences of SEQ ID NO. 2, 11 and 12 and variants thereof. The present invention also provides nucleic acids encoding the DNA polymerases, a method of producing said DNA polymerases, and compositions, expression vectors and host cells or viruses comprising said DNA polymerases. The present invention also provides uses of said DNA polymerases in nucleotide polymerisation, amplification and sequencing reactions.

The present disclosure relates to a microorganism for producing a mycosporine-like amino acid, and a method for producing a mycosporine-like amino acid using the microorganism. The microorganism of the present disclosure shows an improved ability for producing a mycosporine-like amino acid and thus can be effectively used in the production of a mycosporine-like amino acid.

The present invention relates to methods and engineered microbial hosts useful for treating lignin or a derivative thereof. In some embodiments, the host has one or more exogenous nucleic acid sequences that encode a ligninase (e.g., a laccase and/or a peroxidase).