ORIGINAL PAPER Specific dechlorinase activity in lindane degradation by Streptomyces sp. M7 Sergio A. Cuozzo Æ Graciela G. Rolla ´n Æ Carlos M. Abate Æ Marı ´a J. Amoroso Received: 23 December 2008 / Accepted: 31 March 2009 Ó Springer Science+Business Media B.V. 2009 Abstract Synthesis of dechlorinase in Streptomyces sp. M7 was induced when the microorganism was grown in the presence of lindane (c-hexachlorocyclohexane) as the only carbon source. Activity of cells grown with lindane was about four and half times higher compared to cells grown with glucose. Maximum dechlorinase activity was observed at 30°C in alkaline conditions pH (7.9) and the enzyme did not show cation dependency. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed one differential band with a molecular weight similar to serum albumin (M r 66,200), which corresponded to polynucleo- tide phosphorylase, an enzyme that plays an important role in the regulation system and could be involved in the regulation of the dechlorinase gene. Detected in cell-free extracts were c-pentachlorocyclohexene and 1,3,4,6-tetra- chloro-1,4-cyclohexadiene, both being products of the de- chlorinase activity. This is the first time that the presence of an enzyme with dechlorinase activity has been demon- strated in an actinomycete strain isolated in Tucuma ´n, Argentina. Characteristics of this enzyme revealed that Streptomyces sp. M7 could be useful in the future in bio- remediation of soil or as a biosensor. Keywords Streptomyces Á Dechlorinase Á Lindane Á Biodegradation Introduction Xenobiotic compounds such as organochlorine pesticides constitute a major environmental problem due to their extensive use in the past, pronounced resistance to chem- ical and biological degradation (Miglioranza et al. 2002) and their trend to bioaccumulate in the food chain (Mertens et al. 2006). Contamination with halogenated aliphatic compounds is often considered to be relatively recalcitrant due to the gamma isomer of hexachlorocyclohexane (c-HCH or lindane). There are many reports indicating that this toxic compound is present in soil, water, air, plants, agricultural products, animals, food, microbial environ- ments and humans (Albanis et al. 1998; Hura et al. 1999; Chaile et al. 1999; Waite et al. 2001; Botella et al. 2004). c-HCH, commercially known as lindane, is highly chlori- nated and has been extensively used as a broad-spectrum insecticide against a wide range of soil-dwelling and her- bivorous insects (Phillips et al. 2005). Lindane is consid- ered a potential carcinogen and listed as a priority pollutant by the US EPA (Walker et al. 1999; Tao et al. 2005). c-HCH is a lipophilic compound and therefore tends to accumulate and concentrate in the body fat of animals and humans (Johri et al. 1996, 2000). It has been banned or restricted in Argentina and in approximately other 50 countries. However, c-HCH continues to be a serious tox- icological problem at industrial sites, where the past S. A. Cuozzo Á C. M. Abate Á M. J. Amoroso (&) Planta Piloto de Procesos Industriales y Microbiolo ´gicos- CONICET, Tucuma ´n, Argentina e-mail: amoroso@proimi.org.ar S. A. Cuozzo e-mail: sergio_cuozzo@yahoo.com.ar G. G. Rolla ´n Centro de Referencia para Lactobacilos-CONICET, Tucuma ´n, Argentina S. A. Cuozzo Á C. M. Abate Á M. J. Amoroso Facultad de Bioquı ´mica, Quı ´mica y Farmacia, Universidad Nacional de Tucuma ´n, Avenida. Belgrano y Pje. Caseros T4001 MVB, San Miguel de Tucuma ´n, Argentina 123 World J Microbiol Biotechnol DOI 10.1007/s11274-009-0039-x