摘要:
A polymeric enzyme having a molecular weight higher than or equal to 200,000 and not exhibiting any proteolytic activity on casein derived from a culture of Micrococcus caseolyticus is disclosed, as is a method of producing the enzyme by filtration on gel buffered with an aqueous buffer of an enzymatic system prepared by lyophilization of an aqueous concentrate formed by ultrafiltration of the solution obtained by dissolving, in an aqueous solution of calcium chloride, an enzymatic system precipitated from a supernatant of a micro-organism culture broth by ammonium sulphate, wherein the enzyme is not retained on a gel calibrated for proteins with a molecular weight of between 5,000 and 20,000, buffered with a 20 mM TRIS-HCl buffer, at pH 7.5, containing 1.5 mM calcium chloride, and the enzymatic system is derived from a culture broth of said Micrococcus caseolyticus. The enzyme may be used for the production of aspartame by condensation of L-aspartic acid with methyl DL-phenylalaninate.
摘要:
The invention is directed to a process for the purification of the dextran-sucrase produced by Leuconostoc mesenteroides bacteria.The process according to the invention consists of adding to the culture medium, that contains the extra-cellular enzyme and dextran, a quantity of a PEG type polyether so that, in the medium appear two non miscible phases, that are thus maintained under stirring in order to obtain a good contact. Thereafter the lower dextran phase is separated from the upper polyether phase in order to provide a dextran-sucrase enriched enzymatic preparation.The purified enzyme can be used in the synthesis processes of the dextrans possessing specific molecular weights for certain applications.
摘要:
A bFGF is prepared by:(i) forming an adduct between heparin or heparan sulphate and a bFGF which has the 9-10 Leu-Pro bond;(ii) treating the adduct with pepsin A or cathepsin D, thereby cleaving the said bond; and(iii) releasing from the adduct the bFGF thus obtained.This process may be applied to prepare the 146 amino acid form of bFGF from longer forms of bFGF. It may also be used to produce a single form of bFGF from a mixture of bFGFs whose amino acid sequences differ only by having different N-terminii.
摘要:
The invention relates to the use of prebiotics for the preparation of food or pharmaceutical compositions which are intended for the treatment and/or prevention of hyperglycaemic syndromes and, in particular, for the treatment of Type II diabetes and/or the prevention of the onset of Type II diabetes in patients with a predisposition to developing the type of diabetes. The invention also relates to the food and pharmaceutical compositions containing the prebiotics.
摘要:
Nucleic acid sequences of truncated or mutated alternansucrases, vectors containing these nucleic acids sequences, host cells transformed with the nucleic acid sequences encoding truncated or mutated alternansucrases are provided. Furthermore, a process to recombinantly alternansucrase with a high level of expression, while retaining the enzymatic activity is described.
摘要:
The invention concerns mineral carriers carrying modified silicon grafts. They comprise mineral carriers grafted by silicon derivatives with aromatic amino substituents, modified by substituted or unsubstituted adenine radicals. The carriers are used in chromatography and more particularly in affinity chromatography for the purification of enzymes.
摘要:
Method for preparing the disaccharide α-D-glucopyranosyl-(1→4)-2-N-acetyl-2-deoxy-α-D-glucopyranoside, comprising the step of using a mutant of a wild type glycoside hydrolase.
摘要:
The invention relates to the direct selection of metabolic pathways having a determined function in the transformation of a substrate {Ai} into a target product {B}, which is of interest in the industrial, pharmaceutical or agri-food sectors. More specifically, the invention relates to the detection, within metagenomic libraries, of novel biosynthesis pathways involved in a biochemical reaction having a known product {B}. The selection and characterisation of said novel metabolic pathways enables {B} to be produced enzymatically. The invention provides an alternative to the chemical synthesis of the molecule in question {B}. Moreover, and above all, the invention can be used specifically to target and exploit the only metabolic pathways enabling the transformation of {Ai} into {B}, while eliminating the associated metabolic pathways that can catabolise the target product {B}.
摘要:
The invention concerns the use as molecular vector in pharnaceutical, cosmetic and food products of alkylmonoglucosides of general formula (I) in which R1 is a linear or branched C2-C18 alkyl radical.
摘要:
Method for preparing the disaccharide [α-D-Gldp(1→3)]-α-L-Rhap-YR wherein Y is selected from —O— and —S— and R is selected from the group consisting of: C1-C6 alkyl, C1-C6 alkenyl, aryl, allyl, —CO-alkyl (C1-C6), —CO-alkenyl (C1-C6), —CO-aryl comprising the step of using a mutant of a wild type glycoside hydrolase.