Disclosed is an auto-induction regulatory system based on quorum sensing, comprising luxI, luxR and egfp, wherein, the promoter for controlling the expression of luxI and luxR is selected from P.sub.luxI, P.sub.BB or P.sub.J23100; the promoter for controlling the expression of egfp is selected from P.sub.luxI, P.sub.luxI(T-38C) or P.sub.luxI(C-77T). Also disclosed are an application of the auto-induction regulatory system based on quorum sensing in the automatic regulation of expression of a target gene of engineered Escherichia coli, as well as an application thereof in the preparation of alginate lyase and esterase. Further disclosed are a recombinant expression vector and a recombinant engineered bacterium comprising the auto-induction regulatory system based on quorum sensing.

A composition comprising a first material and a second material, wherein said first material is cross-linkable by a first cross-linking reaction and said second material is cross-linkable by a second cross-linking reaction, wherein said first cross-linking reaction and said second cross-linking reaction are inducible by a common activator.

The disclosure discloses an alginate lyase and application thereof, and belongs to the technical field of biology. The alginate lyase provided by the disclosure has high degradation activity, and the enzyme activity reaches 65 U/mg; the alginate lyase is stable in nature, and the enzyme activity remains 98% or higher of the initial enzyme activity after storage at 4° C. for 18 months; and the alginate lyase has high product specificity. The disclosure uses E. coli as a host to express the alginate lyase derived from V. natriegens, the obtained recombinant E. coli can produce the alginate lyase secreted extracellularly in a conventional LB medium without adding an induction substrate sodium alginate, so the downstream processing technology of protein is simplified, and the disclosure has great industrial application potential.

Compositions including an alginate lyase enzyme and anionic surfactant. Methods of treating fabrics by contacting the fabric with an aqueous wash liquor having the detergent composition therein. The compositions and methods are particularly for improving whiteness of a fabric, improved soil removal from a fabric, for malodour removal from a fabric, for anti-wrinkle benefits, anti-redeposition benefits and/or for improved drying of a fabric.

A composition including an alginate lyase enzyme and cleaning adjunct. Methods of treating surfaces by contacting the surface with an aqueous wash liquor having the detergent composition therein.

Laundry detergent compositions can include an alginate lyase enzyme, nuclease enzyme, and anionic surfactant. Also included are methods of treating fabrics by contacting the fabric with an aqueous wash liquor having the laundry detergent composition which includes an alginate lyase enzyme, nuclease enzyme, and anionic surfactant.

Laundry detergent compositions including alginate lyase enzyme, hexosaminidase enzyme and anionic surfactant. Methods of treating fabrics by contacting the fabric with an aqueous wash liquor having the detergent composition therein. The compositions and methods are particularly for improving whiteness of a fabric, improved soil removal from a fabric, for malodour removal from a fabric, for anti-wrinkle benefits, collar and/or cuff cleaning, anti-redeposition benefits and/or for improved drying of a fabric.

Compositions including an alginate lyase enzyme and anionic surfactant. Methods of treating fabrics by contacting the fabric with an aqueous wash liquor having a detergent composition with an alginate lyase enzyme.

The disclosure provides a novel alginate lyase, whose amino acid sequence is SEQ ID NO: 1. The disclosure further provides a nucleic acid encoding the alginate lyase, which can have the sequence of SEQ ID NO: 2, and may be comprised in a recombinant expression vector. Such an expression vector may be comprised in a host microorganism to express the alginate lyase. Also disclosed are methods of producing the alginate lyase by expression in a host microorganism. The alginate lyase enzyme provided by the disclosure can be used for catalyzing the degradation of sodium alginate to produce unsaturated 2-8 saccharides, among which unsaturated disaccharides and unsaturated trisaccharides can be the main component.

The invention provides a series of peptide signals which, when linked to a polypeptide of interest (POI), ensure that said polypeptide is secreted in high yields by a host cell such as Mycoplasma pneumoniae. The invention also provides fusion proteins tagged with said peptide signals, the nucleic acid sequences coding for them, host cells comprising said tagged fusion proteins and a variety of uses of the fusion proteins and the host cells.