Natural gas marketer Catalyst Energy filed for Chapter 11 bankruptcy protection Wednesday, after its credit evaporated overnight.

Georgia utility regulators, meanwhile, will begin deciding on Friday if Catalyst can continue to sell gas in Georgia.

State law requires marketers to have enough credit to pay for the gas it orders.

Catalyst lost both that required line of credit and its contracted fuel supply this week, as the Wall Street crisis rippled into the energy industry.

The state Public Service Commission can suspend Catalyst’s license and dole out its customers to other marketers. It’s unclear whether the authority of bankruptcy court will supersede the regulators.

The company said it has 30,000 customers in Georgia and $20 million in liabilities.

Catalyst CEO Fernando de Aguero and Steve Moore, its vice president for regulatory affairs, both said the company would work with the PSC to guarantee its customers got service.

“We’re working with the PSC and Atlanta Gas Light to make sure their gas service doesn’t get interrupted,” Moore said.

De Aquero said his company’s bankruptcy stems directly from the meltdown on Wall Street.

“We are all aware of what’s happening with the macro economy,” he said. “And its gone down into the mid-market and now Main Street.”

“It’s very common. It’s going on all over the country right now.”

Catalyst’s credit line and gas supply contracts were both with Constellation Energy, the nation’s largest independent energy marketer.

Constellation was a trading partner of Lehman Brothers. Its stock price collapsed after Lehman Brothers’ demise two weeks ago. Constellation announced it was selling itself to Warren Buffett’s Mid American Holdings for a cheap discount a few days later.

Constellation cut off Catalyst late last week, leaving the marketer scrambling for credit in a market that isn’t giving any.

“The illiquid credit markets have exacerbated the issue,” de Aguero said.

Catalyst entered Georgia’s gas market two years ago, with the objective of building a business serving customers underserved or unwanted by other marketers.

The company offers customer service in a range of languages, in an effort to reach immigrants.

Catalyst also pioneered a prepaid gas plan that allows customers with bad or no credit to pay ahead for their gas.

The prepaid alternative, now adopted by at least one other marketer, gives customers a cheaper alternative to the regulated provider-of-last-resort program, which is the most expensive in the state.

De Aguero said he didn’t know whether other Georgia gas marketers may be exposed to credit and supply problems.

But he said tight credit and volatile fuel prices had been tough on energy retailers nationally for months.

About 20 energy retailers have gone bankrupt, de Aguero said, or had to sell in 2008.