Multidrug- and metal-resistant strains of Klebsiella pneumoniae isolated from Penaeus monodon of the coastal waters of deltaic Sundarban.

Marine shrimp of the species Penaeus monodon were collected from the coastal region (Haroa) of the deltaic Sundarbans of West Bengal, India during the premonsoon period in 1996. Klebsiella pneumoniae was isolated from the alimentary canal and gills of the shrimp as the sole isolate. All 10 isolated strains were resistant to erythromycin (30 micrograms/mL), ampicillin (100 micrograms/mL), furazolidone (100 micrograms/mL), and penicillin (100 IU). These strains were able to grow in the presence of silver (Ag+), cobalt (Co2+), cadmium (Cd2+), nickel (Ni2+), lead (Pb2+), copper (Cu2+), and zinc (Zn2+) at concentrations up to 10 mM. All the strains showed similar plasmid profiles, ranging in sizes from 1.8 to 120 kb. Resistance to lead, cobalt, nickel, and copper was encoded by a 3.5-kb plasmid of K. pneumoniae. Synthesis of a 14-kDa periplasmic protein was increased when they were grown in presence of 10 mM Cu2+.