If you have the right authorisation on a business account you can "direct debit" from any account. It let's you charge a bank account in a similar way as a US creditcard can be charged by number and expiry date. Technically the contract with your bank says you need to have a signed authorisation from the account owner to charge their account, but you don't have to show it to the bank before charging.

The money you get that way isn't guaranteed, the account owner could do a charge back. And if that happens you have to show the signed authorisation from the account owner. If you don't have it, expect your bank to terminate the direct debit ability.