The invention relates to a genetically modified prokaryotic cell capable of improved iron-sulfur cluster delivery, characterized by a modified gene encoding a mutant Iron Sulfur Cluster Regulator (IscR) and one or more transgenes or upregulated endogenous genes encoding iron-sulfur (Fe—S) cluster polypeptides or proteins that catalyze complex radical-mediated molecular rearrangements, electron transfer, radical or non-redox reactions, sulfur donation or perform regulatory functions. The prokaryotic cells are characterized by enhanced activity of these iron-sulfur (Fe—S) cluster polypeptides, enhancing their respective functional capacity, and facilitating enhanced yields of compounds in free and protein-bound forms, including heme, hemoproteins, tetrapyrroles, B vitamins, amino acids, δ-aminolevulinic acid, biofuels, isoprenoids, pyrroloquinoline quinone, ammonia, indigo, or their precursors, whose biosynthesis depends on their activity. The invention further relates to a method for producing said compounds or their precursors using the genetically modified prokaryotic cell of the invention, and the use of the genetically modified prokaryotic cell.

Disclosed are a recombinant microorganism having enhanced L-amino acid productivity, wherein the recombinant microorganism is transformed to have removed or decreased activity of at least one of adenosine deaminase and AMP nucleosidase, and a method of producing an L-amino acid using the recombinant microorganism. The use of the recombinant microorganism may enable the production of the L-amino acid in a highly efficient manner.