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July 14 (Reuters) - Wells Fargo's WFC.N profit jumped in the second quarter as its income from interest payments rose.

The fourth-largest U.S. lender's net income was $6.41 billion, or $2.00 per share, in the three months ended June 30, it said on Tuesday. That compares with $5.49 billion, or $1.60 per share, a year earlier.

Shares of the San Francisco, California-based bank rose 1.4% in premarket trading. The stock had slipped nearly 6% this year through last close, underperforming peers.

The lifting of the $1.95 trillion asset cap last year drew a line under the bank's regulatory constraints and freed Wells Fargo to accelerate CEO Charlie Scharf's growth plans.

The bank has focused on growing its credit card and auto businesses, while also hiring bankers from rivals in its commercial business to drive growth.

U.S. banks have continued to benefit from re-investing cash from maturing low-yielding assets in their investment securities portfolios to higher-yielding paper over time.

Wells Fargo's net interest income (NII), the difference between what a bank earns on loans and pays out on deposits, rose 5% to $12.32 billion in the quarter from a year earlier.

The bank had expected a "step up" in net interest income in the reported quarter.