Abstract: The invention relates to a method for altering a protein X such as to modify the characteristics thereof by a) obtaining the mutants X* of the sequence coding for protein X, by means of aleatory mutagenesis, b) transformation of cells with a phenotype [P-] with vectors comprising the mutated nucleic acids obtained in step (a) which code for proteins X*, where P-signifies that said cells are auxotrophic for substance P, P begin the product of the action of X on the natural substrate thereof S, c) culturing said cells in a medium comprising a substrate S*, S* being an analogue of the natural substrate S of the protein X, d) selection of the cells [P-:: X*] which have survived step c) in which the proteins X* can biosynthesise the product P from the substrate S*.

Abstract: The present invention relates to a method for the in vitro synthesis of deoxyribonucleosides and enzymes suitable for this method.

Abstract: The invention concerns novel polypeptides and their fragments, isolated from Lactobacillus, having at least a N-deoxyribosyl transferase activity, the polynucleotides encoding said polypeptides, cloning and/or expression vectors including said polynucleotides, cells transformed by said vectors and specific antibodies directed against said polypeptides. The invention also concerns a method for enzymatic synthesis of deoxyribonucleosides.

Abstract: The invention concerns a method for producing a cyclic L-amino acid of formula (I), characterised in that it consists in reacting a L-diamino acid of formula (II) or an enantiomeric mixture comprising such a L-diamino acid and a corresponding D-diamino acid in variable proportions, in the presence of an ornithine cyclodeaminase or a polypeptide homologous to the ornithine cyclodeaminase.

Abstract: Eubacterial cells which produce non-formylated proteins, polypeptides and/or peptides and methods for making such non-formylated products. The eubacterial cells may be produced by inactivating or deleting the def (deformylase) and/or fmt (Met-tRNA transformylase) gene(s) from the def-fmt operon of the corresponding wild-type strain.

Abstract: The invention concerns novel polypeptides and their fragments, isolated from Lactobacillus, having at least a N-deoxyribosyl transferase activity, the polynucleotides encoding said polypeptides, cloning and/or expression vectors including said polynucleotides, cells transformed by said vectors and specific antibodies directed against said polypeptides. The invention also concerns a method for enzymatic synthesis of deoxyribonucleosides.

Abstract: The invention concerns novel nucleotide analogues comprising a reactive hydrazide function used as initial synthons for preparing compounds (formula I) capable of inducing mutations or capable of inhibiting a DNA polymerase or a kinase. The invention also concerns nucleic acids comprising said nucleotide and nucleoside analogues.

Abstract: This invention relates to a process for preparing 2?-deoxynucleoside compounds or 2?-deoxynucleoside precursors using 2-dehydro-3-deoxy-D-gluconic acid (usually abbreviated as KDG) or its salts as a starting material. A variety of 2?-deoxynucleosides and their analogues are used as a starting material for synthesis or drug formulation in production of an antiviral, anticancer or antisense agent.

Abstract: The present invention relates to a method for generating a novel form of life comprising the steps consisting of: a) irreversible alteration of the genome of a microbial clone; b) cultivation of a vast population of microbial cells originating from the altered clone obtained in step a) during numerous generations under conditions allowing selection for a higher and stable proliferation rate; c) isolation of descendant clones within the cultivated population of step b) still bearing the alteration of step a).

Abstract: The present invention relates to a method for the in vitro enzymatic synthesis of deoxyribonucleosides and enzymes suitable for this method.

Abstract: The invention relates to a method for artificial in vivo evolution of proteins, said method making it possible to bring about the evolution of a protein X by complementation of a relative protein Y,X and Y both belonging to the same class of enzyme commission (EC) nomenclature or belonging to related classes. The mutants D133E and R104Q of desoxycytidine kinase (DCK) were obtained; both of said mutations result in acquisition of thymidine kinase activity by DCK.

Abstract: The invention relates to the genome sequence and the nucleotide sequences coding for polypeptides of cyanophage S-2L. According to the invention, the polypeptides include, but are not limited to, polypeptides involved in the synthesis, transcription and replication of purine bases. In particular, determining the genome of cyanophage S-2L is useful for supplying genes which, expressed in recombinant bacteria, enable the synthesis of DNA monomers incorporating base D (2,6 diaminopurine instead of base A (adenine), thereby producing chemically-remodelled nucleic acids in the bacteria.

Abstract: The invention concerns novel polypeptides and their fragments, isolated from Lactobacillus, having at least a N-deoxyribosyl transferase activity, the polynucleotides encoding said polypeptides, cloning and/or expression vectors including said polynucleotides, cells transformed by said vectors and specific antibodies directed against said polypeptides. The invention also concerns a method for enzymatic synthesis of deoxyribonucleosides.

Abstract: Eubacterial cells which produce non-formylated proteins, polypeptides and/or peptides and methods for making such non-formylated products. The eubacterial cells may be produced by inactivating or deleting the def (deformylase) and/or fmt (Met-tRNA transformylase) gene(s) from the def-fmt operon of the corresponding wild-type strain.

Abstract: The present invention relates to producing non-formylated proteins and/or peptides in bacterial cells lacking deformylase and/or transformylase.

Abstract: The present invention is directed to a method to diversify the chemical composition of proteins produced in vivo comprising the step of disabling, particularly by mutagenesis, the editing function of one of its aminoacyl tRNA synthetases. The present invention is also directed to nucleic acid sequences encoding such mutated aminoacyl tRNA synthetases having their editing site mutated and capable of mischarging its cognate tRNA with a noncanonical amino acid. Also described herein is an improved method for obtaining transformed cells capable of synthetizing in vivo proteins comprising at least a noncanonical amino acid and their use for the production of such proteins.

Abstract: The invention concerns a method for producing a cyclic L-amino acid of formula (I), characterised in that it consists in reacting a L-diamino acid of formula (II) or an enantiomeric mixture comprising such a L-diamino acid and a corresponding D-diamino acid in variable proportions, in the presence of an ornithine cyclodeaminase or a polypeptide homologous to the ornithine cyclodeaminase.

Abstract: The invention concerns novel nucleotide analogues comprising a reactive hydrazide function used as initial synthons for preparing compounds (formula I) capable of inducing mutations or capable of inhibiting a DNA polymerase or a kinase. The invention also concerns nucleic acids comprising said nucleotide and nucleoside analogues. Among such compounds, can be cited in particular the compound of formula (I).

Abstract: The present invention relates to a method and a device for selecting accelerated proliferation of living cells in suspension. The culture apparatus (2) of the present invention enables cells to proliferate in suspension over unlimited periods of time. Natural selection results in the accumulation of genetic variants which are increasingly better adapted to the chosen culture conditions. The organisms used can be prokaryotic or eukaryotic. The organisms used can be naturally occurring organisms or genetically modified organisms. The culture apparatus of the present invention is also suitable for using continuous, periodical or conditional culture conditions. The physical and chemical characteristics of the culture media used can be chosen by the user. The requirement that a population of cells proliferates exclusively in suspension in continuous culture conditions is satisfied by the periodical transfer of the organism suspension from a first culture vessel into a second culture vessel.

Abstract: The invention concerns mutant prokaryotic cells, in particular E. coli, capable of producing proteins whereof the amino acid sequences comprise at least a non-conventional amino acid, methods for producing and purifying said proteins and the proteins obtained by said methods. The invention also concerns uses of said cells and proteins in different fields such as in therapy, cosmetics, diagnosis or biosynthesis or biodegradation of organic compounds.