An in vivo metabolic approach for deciphering the product specificity of glycerate kinase proves that both E. coli's glycerate kinases generate 2-phosphoglycerate.
Zelcbuch L, Razo-Mejia M, Herz E, Yahav S, Antonovsky N, Kroytoro H, Milo R, Bar-Even A. PLoS One. 2015; 10(3):e0122957. Epub 2015 Mar 30.