Improving cytosolic aspartate biosynthesis increases glucoamylase production in Aspergillus niger under oxygen limitation

Table 1 Profiles of the mutant strains constructed in this study

Mutant strains	Gene overexpressed	Enzyme encoded	Pathway	Related limiting amino acids
OE-ala	An11g02620 (Alanine transaminase)	EC 2.6.1.2	pyr + glu → akg + ala	Alanine
OE-glu	An04g00990 (Glutamate dehydrogenase, gdhA)	EC 1.4.1.4	nh₃ + akg + h+nadph→h₂o + glu + nadp	Glutamate
OE-gly	An05g00410 (Glycine/serine hydroxymethyltransferase)	EC 2.1.2.1	thf + ser → h₂o + gly+metthf	Glycine
OE-asp1	An04g06380 (Mitochondrial aspartate aminotransferase)	EC 2.6.1.1	oa(m) + glu(m)→asp(m) + akg(m)	Aspartate
OE-asp2	An16g05570 (Cytosolic aspartate aminotransferase)	EC 2.6.1.1	oa + glu → asp + akg	Aspartate
CBS-ΔolvA	olvA deletion strain

pyr pyruvate, glu, glutamate, akg 2-Oxoglutarate, ala alanine, thf tetrahydrofolate, ser serine, gly glycine, metthf 5,10-Methylenetetrahydrofolate, oa oxaloacetate, asp aspartate. m (mitochondrion)

ISSN: 1475-2859