Abstract: Described is a process for producing a mutant bacterium which exhibits improved survival and/or growth under a selected growth condition, the process comprising the steps of: (a) generating a pool of mutant bacteria by transposon mutagenesis with an activating transposon (TnA), wherein the TnA comprises a promoter capable of increasing transcription of a gene at or near its insertion site; (b) growing bacteria from the mutant pool under the selected growth condition and under one or more reference conditions to produce two or more test cultures; and (c) comparing the distribution of TnA insertions between test cultures to identify a first class of genes which are disadvantageous for growth and/or survival under the selected growth condition and a second class of genes which are advantageous for growth and/or survival under the selected growth condition.

Abstract: Disclosed are methods related to identifying an essential gene which serves as an antibiotic target in a bacterium.

Abstract: Disclosed are methods related to identifying an essential gene which serves as an antibiotic target in a bacterium.

Abstract: Described is a process for producing a mutant bacterium which exhibits improved survival and/or growth under a selected growth condition, the process comprising the steps of: (a) generating a pool of mutant bacteria by transposon mutagenesis with an activating transposon (TnA), wherein the TnA comprises a promoter capable of increasing transcription of a gene at or near its insertion site; (b) growing bacteria from the mutant pool under the selected growth condition and under one or more reference conditions to produce two or more test cultures; and (c) comparing the distribution of TnA insertions between test cultures to identify a first class of genes which are disadvantageous for growth and/or survival under the selected growth condition and a second class of genes which are advantageous for growth and/or survival under the selected growth condition.

Abstract: Disclosed are methods related to identifying an essential gene which serves as an antibiotic target in a bacterium.

Abstract: Provided are methods for identifying differentially represented genes, the method comprising the steps of generating a pool of mutant bacteria by transposon mutagenesis with an activating transposon (TnA), wherein the TnA comprises a promoter such that transposon insertion into bacterial DNA increases the transcription of a gene at or near the insertion site; growing bacteria from the mutant pool in the presence of different amounts of said antibiotic to produce two or more test cultures; and comparing the distribution of TnA insertions between test cultures.

Abstract: Provided herein are methods, and related compositions for identifying a putative essential gene which serves as an antibiotic target in a bacterium, the method, in some embodiments, comprising (a) generating an antibiotic resistant mutant of the bacterium by a method comprising the step of selecting for growth in the presence of an antibiotic to produce an antibiotic resistant mutant clone (AbR mutant); (b) transforming the AbR mutant with one or more essential genes of the bacterium and a transposon which insertionally inactivates bacterial DNA to produce a pool of transposon mutants which are merodiploid for the one or more essential genes; (c) growing bacteria from the merodiploid pool in the presence of different amounts of the antibiotic to produce two or more test cultures; and (d) comparing the distribution of transposon insertions between the test cultures to identify a putative essential gene serving as a target of the antibiotic in the bacterium.

Abstract: Described is a process for producing a mutant bacterium which exhibits improved survival and/or growth under a selected growth condition, the process comprising the steps of: (a) generating a pool of mutant bacteria by transposon mutagenesis with an activating transposon (TnA), wherein the TnA comprises a promoter capable of increasing transcription of a gene at or near its insertion site; (b) growing bacteria from the mutant pool under the selected growth condition and under one or more reference conditions to produce two or more test cultures; and (c) comparing the distribution of TnA insertions between test cultures to identify a first class of genes which are disadvantageous for growth and/or survival under the selected growth condition and a second class of genes which are advantageous for growth and/or survival under the selected growth condition.

Abstract: Disclosed is a method for identifying an essential gene which serves as an antibiotic target in a bacterium, the method comprising the steps of: (a) generating a pool of mutant bacteria by transposon mutagenesis with an activating transposon (TnA), wherein the TnA comprises a promoter such that transposon insertion into bacterial DNA increases the transcription of a gene at or near the insertion site; (b) growing bacteria from the mutant pool in the presence of different amounts of said antibiotic to produce two or more test cultures; and (c) comparing the distribution of TnA insertions between test cultures to identify a putative essential gene serving as a target of said antibiotic in said bacterium.

Abstract: Disclosed is a method for identifying an essential gene which serves as an antibiotic target in a bacterium, the method comprising the steps of: (a) generating an antibiotic resistant mutant of said bacterium by a method comprising the step of selecting for growth in the presence of said antibiotic to produce an antibiotic resistant mutant clone (AbR mutant); (b) transforming the AbR mutant with: (i) one or more essential genes of said bacterium; and (ii) a transposon which insertionally inactivates bacterial DNA, to produce a pool of transposon mutants which are merodiploid for said one or more essential genes; (c) growing bacteria from the merodiploid pool in the presence of different amounts of said antibiotic to produce two or more test cultures; and (d) comparing the distribution of transposon insertions between test cultures to identify a putative essential gene serving as a target of said antibiotic in said bacterium.

Abstract: The invention provides strains of bacteria, especially enterotoxigenic E. coli, attenuated by mutations in the genes encoding enterotoxins (LT, ST, EAST1) and optionally further attenuated by deletion of additional chromosomal genes. In addition the invention provides strains of attenuated bacteria expressing immunogenic but non-toxic variants of one or more of these enterotoxins. These bacteria are useful as a vaccine against diarrhoeal disease.

Abstract: A bacterial cell which expresses three or more coli surface (CS) antigens and methods of making such a cell. The cell is useful in making vaccines against diarrhea.

Abstract: The invention provides strains of bacteria, especially enterotoxigenic E. coli, attenuated by mutations in the genes encoding enterotoxins (LT, ST, EAST1) and optionally further attenuated by deletion of additional chromosomal genes. In addition the invention provides strains of attenuated bacteria expressing immunogenic but non-toxic variants of one or more of these enterotoxins. These bacteria are useful as a vaccine against diarrhoeal disease.

Abstract: A bacterial cell which expresses three or more coli surface (CS) antigens and methods of making such a cell. The cell is useful in making vaccines against diarrhea.

Abstract: The invention provides strains of bacteria, especially enterotoxigenic E. coli, attenuated by mutations in the genes encoding enterotoxins (LT, ST, EAST1) and optionally further attenuated by deletion of additional chromosomal genes. In addition the invention provides strains of attenuated bacteria expressing immunogenic but non-toxic variants of one or more of these enterotoxins. These bacteria are useful as a vaccine against diarrhoeal disease.

Abstract: A bacterial cell which expresses three or more coli surface (CS) antigens and methods of making such a cell. The cell is useful in making vaccines against diarrhoea.

Abstract: The invention relates to a vaccine comprising a pharmaceutically acceptable carrier or diluent and a bacterium, wherein the bacterium contains (i) a DNA sequence encoding a site-specific recombinase, and (ii) a plasmid comprising a recognition element for the recombinase and a DNA sequence encoding a heterologous polypeptide. The recombinase stabilises inheritance of the plasmid and thereby prevents the bacterium from losing the ability to express the heterologous polypeptide.