"Pro-business" is not always synonymous with "conservative."
Conservatives favor low taxes, fiscal restraint, minimal regulation, and serious respect for private property rights.
Business leaders and chambers of commerce, on the other hand, often want higher taxes, lavish government spending (to pay for pet corporate-welfare projects), extensive regulation (to thwart competitors), and the ability to take other people's property (for purposes of development). Add to that the fact that many so-called chambers of "commerce" are populated with tax-consuming government entities, and it's no surprise at all that leaders of the Oklahoma City and Tulsa chambers recently announced their opposition to tax reduction.
The chambers can still be counted on to be solid on some issues (e.g., lawsuit reform and Right to Work). But make no mistake: they're not conservative.