Nocardia iowensis sp. nov., an organism rich in biocatalytically important enzymes and nitric oxide synthase

Abstract

Nocardia strain NRRL 5646, isolated from a garden soil sample in Osceola, Iowa, USA, was initially of interest as an antibiotic producer. It contained biocatalytically important enzymes and represented the first described nitric oxide synthase enzyme system in bacteria. The present polyphasic taxonomic study was undertaken to differentiate strain NRRL 5646T from related species of the genus Nocardia. Chemotaxonomic analyses included determinations of the fatty acid methyl ester profile (C 16 : 1 v6c/C 16 : 1 v7c, C 16 : 0 , C 18 : 1 v9c and C 18 : 0 10-methyl as major components), quinone [cyclo MK-8(H 4 ) as the major component], polar lipid (diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside as major components) and mycolic acid. These results supported its placement within the genus Nocardia. Biochemical testing and 16S rRNA, 65-kDa heat-shock protein (hsp65) and preprotein translocase (secA1) gene sequence analyses differentiated strain NRRL 5646 T from recognized Nocardia species. Previous studies have demonstrated that other genetic sequences (carboxylic acid reductase, Nocardia phosphopantetheinyl transferase and GTP cyclohydrolase I) from strain NRRL 5646 T can also be used to substantiate its uniqueness. The level of 16S rRNA gene sequence similarity between strain NRRL 5646 T and the type strains of Nocardia tenerifensis and Nocardia brasiliensis was 98.8 %. However, strain NRRL 5646 T could be clearly distinguished from these Nocardia species based on DNA-DNA hybridization data. Consequently, strain NRRL 5646 T is considered to represent a novel species of the genus Nocardia, for which the name Nocardia iowensis sp. nov. is proposed. The type strain is NRRL 5646 T (5UI 122540Strain NRRL 5646 T was initially identified as an antibioticproducing bacterium isolated from a garden soil sample in Osceola, Iowa, USA (Hlavka & Bitha, 1977;Martin et al., 1977). This strain showed an extraordinary diversity of biotransforming enzymes and the first bacterial nitric oxide synthase (NOS) system with possible physiological importance, making its identification to the species level important. Strain NRRL 5646 T converts many natural and synthetic organic compounds into valuable products, including flavonoids (Herath et al., 2006;Maatooq & Rosazza, 2005), vanillic acid (Dhar et al., 2007) and 4-vinylphenol (Lee &Rosazza, 2002). A novel ATP/NADPHdependent carboxylic acid reductase was isolated from strain NRRL 5646T (Li & Rosazza, 1997) and subsequently cloned (car; GenBank accession number AY495697; He et al., 2004a). The reduction system required a phosphopantetheinyl transferase (npt, GenBank accession number DQ904035; Venkitasubramanian et al., 2007). Strain NRRL 5646 T contains the first NOS system characterized in prokaryotes (Chen & Rosazza, 1995). As part of the NOS system, strain NRRL 5646 T contains guanylate cyclase for cyclic GMP synthesis (Son & Rosazza, 2000), and GTP cyclohydrolase I (gch; GenBank accession number Abbreviation: NOS, nitric oxide ...

Comparison of three phenotypic and deoxyribonucleic acid extraction methods for isolation and Identification of Nocardia spp

“…In further studies, we must do molecular tests according to 16S rDNA sequencing, for precisely identification of Nocardia species. [ 13 29 30 31 ]…”

Laboratory Maintenance of Nocardia Species

“…have been profusely studied for their ability to produce novel bioactive substances with antibacterial, anticancer, and immunosuppressant activities (Aoki et al, 1976;Murakami et al, 1996;Shigemori et al, 1996;Shigemori et al, 1998;Igarashi et al, 2000;Li et al, 2003;Sohng et al, 2008). In addition, they are used in the biotransformation of natural products (Li and Rosazza, 2000;Sharma et al, 2011;Sharma et al, 2012) and the biodegradation of xenobiotics (Xiong et al, 2005;Zeinali et al, 2007;Le et al, 2010;Luo et al, 2013), as well as in industrial processes as a source of enzymes (Khan et al, 1998;Wang et al, 2006;Lamm et al, 2009). Nocardia sp.…”

Nocardia aciditolerans sp. nov., isolated from a spruce forest soil

“…Saprophytic nocardiae have received less attention though they are widely distributed in natural habitats, notably soil, where they have a role in the turnover of organic matter (Orchard 1979, 1981). There is evidence that some species synthesize bioactive compounds of potential industrial value, as exemplified by Nocardia iowensis (Lamm et al 2009). …”