The present invention provides a 5-methylfolate producing microorganism which a) has been modified to have a decreased expression and/or activity of a polypeptide having both dihydrofolate synthase activity and folylpolyglutamate synthetase activity compared to an otherwise identical microorganism (reference microorganism); b) has been (further) modified to express a heterologous polypeptide having only dihydrofolate synthase activity; c) has been (further) modified to have an increased expression level of at least one enzyme (such as at least two, at least three, at least four, at least five, at least six, at least seven or at least eight) enzymes involved in the biosynthesis of a 5-methylfolate compared to an otherwise identical microorganism (reference microorganism); and/or d) has been (further) modified to have a decreased expression and/or activity of a polypeptide having 5-methyltetrahydropteroyltriglutamate-homocysteine S-methyltransferase activity compared to an otherwise identical microorganism (reference microorganism).

Provided is a vector capable of co-expressing two different target proteins on the microbial surface using two promoters derived from Lactobacillus, and a method of expressing target proteins on the microbial surface using the vector. The vector containing foreign genes inserted therein is transformed into a microorganism, and allows different foreign proteins to be stably expressed on the surface of the microorganism. Furthermore, provided is a surface expression vector containing the gene pgsA encoding a poly-gamma-glutamate synthetase complex, and a method of expressing a target protein on the microbial surface using the vector. The vector containing foreign genes inserted therein is transformed into a microorganism, and allows the foreign proteins to be stably expressed on the surface of the microorganism.

A genetically modified diazotrophic microbe is genetically modified to produce ?-polyglutamic acid (?-PGA). In one or more embodiments, the diazotrophic microbe is Azotobacter vinelandii. In one or more embodiments, the diazotrophic microbe is genetically modified to use a non-sugar carbon source.

The present invention relates to a recombinant microorganism with the controlled ability to produce polyols or exopolymers. The present invention also relates to a selective production or simultaneous production method for polyols or exopolymers using the recombinant microorganism of the present invention.