The present disclosure relates to engineered penicillin G acylase (PGA) enzymes having improved properties, polynucleotides encoding such enzymes, compositions including the enzymes, and methods of using the enzymes.

The present invention provides engineered penicillin G acylase (PGA) enzymes, polynucleotides encoding the enzymes, compositions comprising the enzymes, and methods of using the engineered PGA enzymes.

The present disclosure relates to engineered penicillin G acylase (PGA) enzymes having improved properties, polynucleotides encoding such enzymes, compositions including the enzymes, and methods of using the enzymes.

The present invention provides engineered penicillin G acylase (PGA) enzymes, polynucleotides encoding the enzymes, compositions comprising the enzymes, and methods of using the engineered PGA enzymes.

The present invention provides engineered penicillin G acylase (PGA) enzymes having improved properties, polynucleotides encoding such enzymes, compositions including the enzymes, and methods of using the enzymes.

The invention provides probes with formula (I):

##STR00001##

in which: X.sub.1NH, O, or S; X.sub.2O or S; SE is a labile group, which may be eliminated under the action of a stimulus that may in particular be the presence of an enzyme, a chemical compound, or a physicochemical characteristic of the medium in which the probe is located; A is an aromatic group that, following cleavage of the C(X.sub.2)O bond in aqueous solution, leads to the liberation of a chromophore or a fluorophore, R represents a hydrogen atom or -(L)n-GP, in which n is equal to 0 or 1, L is a linker arm, and GP is a hydrosolubilizing group; as well as their physiologically acceptable salts, solvates, or hydrates. The invention also provides intermediates for the synthesis thereof and detection methods employing them.

The present disclosure relates to an enzyme-immobilized porous membrane and a preparation method of antibiotics using the same, and more specifically, to an enzyme-immobilized porous membrane prepared by immobilizing a specific enzyme through dead-end filtration, and a preparation method of antibiotics with a high yield using the enzyme-immobilized porous membrane.

According to various exemplary embodiments of the present disclosure, the enzyme capable of promoting the synthesis reaction of the antibiotic substance is able to be stably immobilized in the porous membrane by passing the solution of enzyme through the membrane.

In addition, it is possible to provide antibiotics with a high yield by preparing the antibiotics by passing the reactant solution through the enzyme-immobilized porous membrane.

The present invention relates to 25 hitherto undescribed genes of B. licheniformis and gene products derived thereform and all sufficiently homologous nucleic acids and proteins thereof. They occur in five different metabolic pathways for the formation of odorous substances. The metabolic pathways in question are for the synthesis of: 1) isovalerian acid (as part of the catabolism of leucine), 2) 2-methylbutyric acid and/or isobutyric acid (as part of the catabolism of valine and/or isoleucine), 3) butanol and/or butyric acid (as part of the metabolism of butyric acid), 4) propyl acid (as part of the metabolism of propionate) and/or 5) cadaverine and/or putrescine (as parts of the catabolism of lysine and/or arginine). The identification of these genes allows biotechnological production methods to be developed that are improved to the extent that, to assist these nucleic acids, the formation of the odorous substances synthesised via these metabolic pathways can be reduced by deactivating the corresponding genes in the micro-organism used for the biotechnological production. In addition, these gene products are thus available for preparing reactions or for methods according to their respective biochemical properties.

The present disclosure relates to engineered penicillin G acylase (PGA) enzymes having improved properties, polynucleotides encoding such enzymes, compositions including the enzymes, and methods of using the enzymes.

A method for separating amoxicillin and phenylacetic acid from reaction solution in one-step enzymatic synthesis of amoxicillin is provided. The method employs immobilized penicillin acylase mutant to catalyze the one-step synthesis of amoxicillin from penicillin potassium, and develops a separation process for the resulting reaction mixture. The technical scheme mainly comprises: Firstly separating the immobilized penicillin acylase mutant from the reaction solution through filtration; subsequently isolating amoxicillin via crystallization; followed by separating and recovering phenylacetic acid through toluene extraction and back extraction. This separation method enables rapid and efficient isolation of amoxicillin with high production yield, achieving an average crystallization rate of 93.22%. Concurrently, it demonstrates effective separation and recovery of phenylacetic acid while allowing recyclable use of the toluene extractant.