Marcelline started studying violin under her uncle Joseph Galea, sub-principal of the Manoel Theatre Orchestra. She furthered her studies under Guido Mamo, Mario Bisazza, Joachim Atanassov, and participated in masterclasses with Ursula Gorniak and Richard Deacon (UK). In 1984, Marcelline joined the Orchestra under Mro. J. Sammut, and in 1993 was appointed Concertmaster, a position she still presently holds.

In 2006, she performed in Paris, with the World Philharmonic Orchestra. She toured leading the Malta Philharmonic Orchestra, performing in Europe, Russia, China and the United States of America.

Marcelline is also a member of the Valletta Baroque Ensemble, and attended Baroque masterclasses in Malta and Marnaves (France).

Apart from performing and recording orchestral repertoire, both in Malta and abroad, Marcelline is a very active chamber musician and soloist.