Roth IRA backdoor conversation when i have a SEP

Hi,

 

I have a existing SEP and want to do a backdoor Roth IRA.  If i roll the SEP into my employers 401K plan at that point i will no longer have any other IRA.  Am i able to do the traditional IRA with after TAX dollars to Roth conversation without any taxable penalties sine there is no other IRA?

 

thank you

 

allen