In continuation of the collaborative project initiated by Dr. Vanaja Kumar on developing new luceferase reporter phage (LRP) constructs at Dr. William Jacobs Jr.'s laboratory, Dr. Kandasamy Jayasankar's work was aimed at "Development of reporter phages for detection of Mycobacterium tuberculosis for use in a diagnostic kit to detect drug-resistant variants." A mycobacteriophage infecting M. tuberculosis, BxZ2 was isolated from the soil of Bronx zoo and its temperate nature was observed at TRC.
It was hypothesized that a LRP construct of a temperate phage will be very useful with higher sensitivity, in the diagnosis of tuberculosis on clinical specimens. At the laboratory of Dr. William Jacobs Jr., the LRP construction of the temperate phage BxZ2 and that of 2 new lytic mycobacteriophages, Che3 and Che6 were undertaken. These constructs were then brought to TRC, Chennai and their sensitivity in detecting tubercle bacilli from clinical samples was compared with that of the regular LRPs of TM4 and D29 (phAE80 and phAE 129). However, it was observed that none of the new constructs, neither the temprate nor the lytic ones, had improved sensitivity over phAE129. This finding led to further efforts of improving the sensitivity of the diagnostic test by developing new constructs of mycobacteriophages with β-galactosidase gene and icl and acr promoters.
Dr. Kandasamy Jayasankar participated in the Einstein AITRP's in-country workshop conducted in 2004.