Gentech International in Girvan, which makes sensors used in 95% of America's trucks, is shedding its entire staff.
The announcement comes just days after aviation firm GE Caledonian said it was slashing 82 jobs at Prestwick.
Ayr, Carrick and Cumnock MP Sandra Osborne said: "This is another bitter blow to the area and, with the economy in its current state, could not come at a worse time.
"I am in contact with the company and will be meeting them next week.
"I hope some operations and jobs can be retained by other means.
"I have contacted Scottish Enterprise Ayrshire and South Ayrshire Council and will continue to do what I can to ensure the workforce receives all the support and assistance required."
US firm Measurement Specialities bought Gentech in 2011 but have hundreds of people working on sensors at their Chinese factories.