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The activity of the QUTR transcription repressor protein in the quinic acid utilization pathway of Aspergillus nidulans nullifies the action of the QUTA activator protein. Genetic analyses suggest three mechanisms of action of the QUTR protein. The first indicates that high levels of QUTR protein result in the formation of another protein that interacts with QUTA protein to inactivate it. The second possibility is the production of a pool of organic molecules that inactivate QUTA and the third is an inactivating effect through a protein-protein interaction with the QUTA protein.

Previous research has shown that the expression of the eight genes of the quinic acid utilization (qut) gene cluster in Aspergillus nidulans is regulated by a positively acting regulatory protein named QUTA. To better understand the mechanism, the domain structure and function within the QUTA protein is analyzed. Northern blot experiments with messenger RNA support the view that the protein regulates the expression of the qut gene cluster. Western-blot and zinc-binding experiments show that zinc is binded in vitro by a putative zinc binuclear cluster motif within the N-terminus of the protein.

Pre-chorismate shikimate pathway shares two metabolites, 3-dehydroquinate and dehydroshikimate, with the quinate pathway. The enzymes involved in catalyzing the pathway are monofunctional and built around structural modules. The entire quinate pathway is composed by co-option of preformed domains from associated pathways. Domain structure within the AROM protein reveals a dimer of identical subunits with interfacing between two DHQ synthase domains. The pathway can be modulated using principles of metabolic control analysis.