Characterization and Culture on Sugarcane Molasses of Gordonia Polyisoprenivorans CCT 7137, a New Strain Isolated from Contaminated Groundwater in Brazil

Abstract

The actinomycete strain Lg, which was isolated from groundwater contaminated with leachate flowing out of a former municipal landfill site (upstate Sa˜o Paulo, Brazil) and found to produce exopolysaccharides, was analysed by polyphasic taxonomy. The growth of this strain on sugarcane molasses, at various concentrations from 2% to 10%, and on the standard glucose-yeast-maltose (GYM) medium was observed by monitoring the optical density of the culture at 600 nm. Lg was found to be Gram-positive, catalase-positive, oxidase-negative, non-motile, non-sporing and did not reduce nitrate. Morphological, biochemical, chemotaxonomic and molecular tests indicated that Lg has properties typical of Gordonia polyisoprenivorans and this new strain was thus named G. polyisoprenivorans CCT 7137. Growth of the bacterium in the experimental media was notably affected by the molasses content, being fastest at 2% and 3%, the lowest contents, the maximum specific growth-rates being 0.157 h )1 and 0.168 h )1 , respectively. These rates were greater than those achieved at higher concentrations and of the same order as the rate in GYM medium, 0.175 h )1 . CCT 7137 is one of six strains of G. polyisoprenivorans so far isolated and recorded in the literature, and one of the two found in contaminated groundwater. This is the first known study of the growth of a strain of G. polyisoprenivorans in GYM medium and on sugarcane molasses as sole source of nutrients. The latter is proposed as a potential substrate for production of this strain.

Gordonia polyisoprenivorans from groundwater contaminated with landfill leachate in a subtropical area: characterization of the isolate and exopolysaccharide production

“…In a study on the effect of bacterial EPS on the hydraulic conductivity of porous media, Vandevivere and Baveye (41) reported that EPS in the free form exerted a much stronger influence than capsular EPS. The maximum specific growth rate of Lc strain in E medium with glucose in anaerobic conditions (μ max = 0.17 h -1 ) was similar to those measured for G. polyisoprenivorans CCT 7137 in GYM (μ max = 0.175 h -1 ) and in sugarcane molasses 2% (μ max = 0.157 h -1 ) and 3% (μ max = 0.168 h -1 ), in aerobic conditions (15). The ability to grow and produce EPS in anaerobic conditions in the laboratory is a fundamental requirement if an organism is to produce the metabolite in situ, or even for low-cost production at laboratory scale.…”

“…In contrast to the first strain isolated from this source, G. polyisoprenivorans CCT 7137 (15), which produced only smooth colonies, strain Lc produced some rough variants. The ability of strains of G. polyisoprenivorans to produce smooth and rough variants was previously noted in strains VH2 (2,23) and Y2K (2).…”

“…To determine the total EPS, samples were heated for 60 minutes in a boiling water bath to free and dissolve capsular EPS. Both total and free EPS were quantified directly by the phenol-sulfuric acid method and capsular EPS was determined by subtracting the free EPS concentration from the total (15). The values shown for EPS were calculated by subtracting the amount of background interference in fresh media from that detected in cultures broth (3,22).…”

Peningkatan Populasi, Pertumbuhan dan Serapan Nitrogen Tanaman Kedelai dengan Pemberian Azotobacter Penghasil Eksopolisakarida

“…Eksopolisakarida disintesis di dalam sitoplasma bakteri dari gula glukosa (Schimd et al, 2015) dan nitrogen berperan dalam pembentukan EPS (Gutiérrez-Rojas et al, 2011). Konsentrasi gula di molase dapat mencapai 71.2% (Fusconi et al 2005) namun kadar N-NO 3 hanya 0.025% (Younis et al, 2010) sehingga NH 4 Cl menginduksi sintesis EPS. Konsentrasi EPS di media molase + NH 4 Cl jauh lebih tinggi daripada di media Vermani (Vermani et al, 1997) yang telah digunakan untuk untuk menginduksi sintesis EPS (Hindersah dan Sudirja, 2012).…”

Starvation survival of Gordonia polyisoprenivorans CCT 7137, isolated from contaminated groundwater in Brazil

“…In our laboratory, Gordonia polyisoprenivorans (CCT 7137) was isolated as an EPS-producing strain and has been investigated concernig its ability to grow and produce EPS from sugarcane molasses as sole nutrient source, aiming at future tests in porous medium for EPS production in situ (Fusconi and Godinho 2002;Fusconi 2005;Fusconi et al 2005). In this light, the present work aims at evaluating the behavior of G. polyisoprenivorans CCT 7137, under starvation to be applied to biobarrier process formation.…”