Single copy Distributed Software Transactional Memory protocol maintains only one replica of each object in the system and is therefore prone to failures in large scale dynamically changing network. In this paper we propose a replication model using quorum system for transactional memory protocol where communication among the nodes takes place using gossip. The previous protocols demand a static structure over the network. Maintenance of a static structure for a dynamic network requires a significant overhead. Our method executes on an unstructured network which does not require adaption in case of node joining and node leaving. The algorithm maintains the coherence of the objects and aims to achieve low communication cost while reducing execution time of the transactions. The algorithm achieves a message complexity of $$ {\text{O}}\left( {\sqrt n } \right) $$ and time complexity of $$ {\text{O}}\left( {\log \sqrt n } \right) $$ which is an improvement over previous replication protocols for distributed transactional memory. Simulation results shows that the method exhibits better fault tolerance and requires less number of messages than existing approaches.