Mo. Rev. Stat. § 400.9-201: General effectiveness of security agreement.

(a) Except as otherwise provided in chapter 400, a security agreement is effective according to its terms between the parties, against purchasers of the collateral, and against creditors.

(b) A transaction subject to this article is subject to any applicable rule of law which establishes a different rule for consumers.

(c) In case of conflict between this article and a rule of law, statute, or regulation described in subsection (b), the rule of law, statute, or regulation controls. Failure to comply with a statute or regulation described in subsection (b) has only the effect the statute or regulation specifies.

(d) This article does not:

(1) Validate any rate, charge, agreement, or practice that violates a rule of law, statute, or regulation described in subsection (b); or

(2) Extend the application of the rule of law, statute, or regulation to a transaction not otherwise subject to it.