This invention relates to polypeptides having aldolase activity, including pyruvate activity such as, without limitation, HMG and/or KHG aldolase activity, polynucleotides encoding these polypeptides, and methods of making and using these polynucleotides and polypeptides. In some embodiments, the invention is directed to polypeptides having aldolase activity, including pyruvate activity such as, without limitation, HMG and/or KHG aldolase activity, including thermostable and thermotolerant activity, and polynucleotides encoding these enzymes, and making and using these polynucleotides and polypeptides. The polypeptides in accordance with the invention can be used in a variety of pharmaceutical, agricultural and industrial contexts. In some embodiments, the invention provides polypeptides and biosynthetic pathways that are useful in the production of R-2-hydroxy 2-(indol-3ylmethyl)-4-keto glutaric acid (R-MP) and certain stereoisomers of monatin, such as R,R and S,R monatin, and salts thereof, as well as certain stereoisomers of monatin derivatives, such as the R3R and S5R configurations, and salts thereof.
