title: Isolation and identification of Aeromonas caviae strain KS-1 as TBTC- and lead-resistant estuarine bacteria.
abstract: Tributyltin chloride (TBTC)- and lead-resistant estuarine bacterium from Mandovi estuary, Goa, India was isolated and identified as Aeromonas caviae strain KS-1 based on biochemical characteristics and FAME analysis. It tolerates TBTC and lead up to 1.0 and 1.4 mM, respectively, in the minimal salt medium (MSM) supplemented with 0.4 % glucose. Scanning electron microscopy clearly revealed a unique morphological pattern in the form of long inter-connected chains of bacterial cells on exposure to 1 mM TBTC, whereas cells remained unaltered in presence of 1.4 mM Pb(NO₃)₂ but significant biosorption of lead (8 %) on the cell surface of this isolate was clearly revealed by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. SDS-PAGE analysis of whole-cell proteins of this lead-resistant isolate interestingly demonstrated three lead-induced proteins with molecular mass of 15.7, 16.9 and 32.4 kDa, respectively, when bacterial cells were grown under the stress of 1.4 mM Pb (NO₃)₂. This clearly demonstrated their possible involvement exclusively in lead resistance. A. caviae strain KS-1 also showed tolerance to several other heavy metals, viz. zinc, cadmium, copper and mercury. Therefore, we can employ this TBTC and lead-resistant bacterial isolate for lead bioremediation and also for biomonitoring TBTC from lead and TBTC contaminated environment.
authors.affiliation: Laboratory of Bacterial Genetics and Environmental Biotechnology, Department of Microbiology, Goa University, Taleigao Plateau, Goa 403206, India.
authors.forename: Kashif
authors.initials: K
authors.lastname: Shamim
authors.forename: Milind Mohan
authors.initials: MM
authors.lastname: Naik
authors.forename: Anju
authors.initials: A
authors.lastname: Pandey
authors.forename: Santosh Kumar
authors.initials: SK
authors.lastname: Dubey
mesh_terms: D000222:Adaptation, Physiological; D057585:Aeromonas caviae / Q000302:isolation & purification / Q000502:physiology*; D001673:Biodegradation, Environmental; D007194:India; D007854:Lead / Q000032:analysis / Q000633:toxicity*; D014220:Trialkyltin Compounds / Q000032:analysis / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D014220:Trialkyltin Compounds; D014874:Water Pollutants, Chemical; D007854:Lead; C011559:tributyltin