Perfect Kozak is not as short as CCACC. In your case, if upstream of the CACC is a G instead of A, downstream of ATG is also a G, it maybe works (less) efficiently; otherwise, I would reconstruct again.
g*r
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Kozak Sequence for Mammalian Expression If you will be recombining your entry clone with a destination vector for mammalian expression, your insert should contain a Kozak consensus sequence with an ATG initiation codon for proper initiation of translation (Kozak, 1987; Kozak, 1991; Kozak, 1990). An example of a Kozak consensus sequence is provided below. Other sequences are possible, but the G or A at position -3 and the G at position +4 are the most critical for function (shown in bold). The AT