Role of heavy metal resistant Ochrobactrum sp. and Bacillus spp. strains in bioremediation of a rice cultivar and their PGPR like activities

Abstract

The present study demonstrates the metal toxicity ameliorating and growth promoting abilities of three different bacterial isolates when applied to rice as host plant. The three bacterial strains included a cadmium resistant Ochrobactrum sp., a lead resistant Bacillus sp. and an arsenic resistant Bacillus sp. designated as CdSP9, PbSP6, and AsSP9, respectively. When these isolates were used as inocula applied to metal-treated rice plants of variety Satabdi, the germination percentage, relative root elongation (RRE), amylase and protease activities were increased. The toxic effect of metal was reduced in presence of these bacteria. The overall biomass and root/shoot ratio were also enhanced by bacterial inoculation. Hydroponic studies showed that the superoxide dismutase (SOD) activity and malondialdehyde (MDA) level, which had been increased in the presence of metal stress in rice roots, were lowered by the bacterial inoculation. In addition, all three strains were 1-aminocyclopropane-1-carboxylate (ACC) deaminase and catalase positive, whereas siderophore producing ability was lacking in PbSP6. However, both PbSP6 and AsSP9 were protease positive and could hydrolyse starch. The data indicate that these bacteria have promise for bioremediation as well as for plant growth promotion.

Characterization of ACC Deaminase producing B. cepacia, C. feurendii and S. marcescens for Plant Growth Promoting activity

“…Conc. of the proteins in the pellet was determined and the amount of IAA produced was expressed in µg/mg cell protein (Pandey et al, 2013).…”

“…Siderophore (Ali et al, 2014), HCN (Ali et al, 2014), Chitinase (Vyas and Deshpande, 1989), Protease (Pandey et al, 2013), Phosphate solubilization (Gaur, 1990), Cellulase (Samanta et al, 1989) and Lipase (Cowan, 1974) production were performed for better understanding of selected rhizobacterial strains Characterization of partially purified ACC deaminase enzyme ACC deaminase assay was and purification was done by ammonium sulfate precipitation method followed by dialysis (Verma et al, 2011) Silica based column chromatography was performed from dialysis sample by Plugging a Pasteur pipette with a small amount of cotton; a wood applicator stick was used to tamp it down lightly. Silica gel (10gm) was taken and mixed in Sodium phosphate buffer properly and pour the gel in Pasteur pipette using a 10 ml beaker.…”

Untitled

“…Moreover, the use of Ochrobactrum sp. for phytoremediation of heavy metal or other organic pollutants have also been studied (Imran et al, 2014;Pandey et al, 2013). Previous studies show that Ochrobactrum sp.…”

“…The genus Ochrobactrum was firstly described by Holmes et al (1988) and a large number of its isolates were collected from soil samples and wheat roots (Lebuhn et al, 2000) for promoting plant growth (Pandey et al, 2013). Moreover, an effective plant-growth promoting bacterium, Ochrobactrum sp.…”

Pesquisa de infecção por Brucella spp. em botos-vermelhos (Inia geoffrensis) de vida livre, procedentes da reserva de desenvolvimento sustentável de Mamirauá, Tefé, Amazonas, Brasil

“…O gênero Brucella tem sido considerado um gênero bacteriano em expansão, em razão das novas variantes e espécies identificadas em várias espécies de hospedeiros silvestres nas últimas décadas (BARUN et al, 2007;FOSTER et al, 2007;SCHLABRITZ-LOUTSEVITCH et al, 2009;SCHOLZ et al, 2009SCHOLZ et al, , 2010EISENBERG et al, 2013 HUBER et al, 2010), vegetais (TRUJILLO et al, 2005TRIPATHI et al, 2006;ZURDO-PINERO et al, 2007;KAMPFER et al, 2008;IMRAN et al, 2010), plantas de tratamento de esgotos e águas residuárias WOO et al, 2011), humanos (MOLLER et al, 1999;MAHMOOD et al, 2000;STIAKAKI et al, 2002;TEYSSIER et al, 2007;DHARNE et al, 2008;HAGIYA et al, 2013;MATTOS et al, 2013; SITI ROHANI E TZAR, 2013) e animais (KAMPFER et al, 2003(KAMPFER et al, , 2011EL ADAWY et al, 2012). Algumas espécies do gênero vêm sendo estudadas pelo potencial de aplicação como biorremediadores ou como bactérias promotoras de crescimentos para plantas (PANDEY et al, 2013 (MOLLER et al, 1999;MAHMOOD et al, 2000;STIAKAKI et al, 2002;DHARNE et al, 2008;HAGIYA et al, 2013;MATTOS et al, 2013;ROHANI;TZAR, 2013 (ELSAGHIR et al, 2003;HOVART et al, 2011 Atualmente, a família Propionibacteriaceae é composta por 15 gêneros bacterianos: Propionibacterium (CHARFREITAG et al, 1988), Luteococcus COLLINS et al, 2000), ...…”