Improved production of threonine from E. coli by fermentation is accomplished by attenuation but not elimination of the expression of either or both of the yafV gene encoding omega-amidase (a.k.a. 2-oxoglutaramate amidase). In certain embodiments the strain also has attenuated expression of the ilvA gene encoding threonine dehydratase (a.k.a threonine deaminase) in cases where there is attenuated express of the ilvA gene there is no need to express an exogenous cimA gene. In examples of both cases, attenuation is accomplished by engineering these genes to contain a weaker ribosome site. Further improvements in threonine production are made by expression of a heterologous pyruvate carboxylase gene exemplified by expression of the Corynebacterium glutamicum pyc gene under control of an E. coli promoter, to provide expression of pyruvate carboxylase that is not naturally expressed in E. coli. Still further improvement is accomplished by overexpression of the rhtC gene encoding the E. coli threonine transporter protein, exemplified by inserting a stronger ribosome binding site upstream of the open reading frame for the rhtC gene.

A method of engineering bacteriophages comprising isolating a bacteriophage; removing all attachment genes from a genome of said bacteriophage; inserting a first unique open reading frame encoding one or more attachment genes and inserting a second unique open reading frame encoding one or more genes useful for overcoming bacterial defenses; and inserting a non-natural attachment gene into said first open reading frame, wherein said non-natural attachment gene is specific for attaching to a selected bacteria.

Improved production of threonine from E. coli by fermentation is accomplished by attenuation but not elimination of the expression of either or both of the yajV gene encoding omega-amidase (a.k.a. 2-oxoglutaramate amidase) and the ilvA gene encoding threonine dehydratase (a.k.a threonine deaminase). In cases where there is attenuated expression of the ilvA gene, there is no need to express an exogenous cimA gene. In examples of both cases, attenuation is accomplished by engineering these genes to contain a weaker ribosome site. Further improvements in threonine production are made by expression of a heterologous pyruvate carboxylase gene exemplified by expression of the Corynebacterium glutamicum pyc gene under control of an E. coli promoter, to provide expression of pyruvate carboxylase that is not naturally expressed in E. coli.