Leu Gene clusters

While a gene cluster might be an operon, it can be referred to as an operon in the strict sense of the Jacob-Monod model only if certain predictions of the model are met [1]. The evidence that the leu gene cluster is, in fact, an operon is as follows ... 

Other than the apparent arrangement of the genes in an operon, there is no evidence that any other features of the Jacob-Monod model are involved in expression of the leu genes. Although the cluster is repressed... 

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