Fig. 1

ʟ-Ornithine biosynthesis metabolic pathways in C. glutamicum and strategies to improve ʟ-ornithine accumulation. The red × represented this pathways were inactivated. The blue font and arrows represented that pathways were attenuated. The green font and arrows indicated that pathways were overexpressed. The genes encoding enzymes involved in catalytically relevant reactions. pgi, encodes glucose-6-phosphate isomerase; zwf, encodes glucose-6-phosphate dehydrogenase; pgl, encodes 6-phosphogluconolactonase; tkt, encodes transketolase; tal, encodes transaldolase; opcA, encodes the putative glucose-6-phosphate dehydrogenase assembly protein; pfkA, encodes ATP-dependent phosphofructokinase; gap, encodes glyceraldehyde 3-phosphate dehydrogenase; pyk, encodes pyruvate kinase; pta, encodes phosphotransacetylase; ackA, encodes acetate kinase; cat, encodes succinyl-CoA:acetate CoA-transferase; ncgl2228, encodes a putative branched amino acid transporter protein; odhA, encodes a subunit of 2-ketoglutarate dehydrogenase; gdh, encodes glutamate dehydrogenase; ncgl1221, encodes glutamate transporter; proB, encodes gamma-glutamate kinase; cg3035, encodes N-acetylglutamate synthase; argB, encodes N-acetylglutamate kinase; argC, encodes N-acetyl-gamma-glutamylphosphate reductase; argD, encodes acetylornithine aminotransferase; argF, encodes ornithine carbamoyltransferase; argJ, encodes ornithine acetyltransferase; argR, encodes arginine repressor; lysE, encodes lysing transporter