title: Nocardiopsis species: Incidence, ecological roles and adaptations.
abstract: Members of the genus Nocardiopsis are ecologically versatile and biotechnologically important. They produce a variety of bioactive compounds such as antimicrobial agents, anticancer substances, tumor inducers, toxins and immunomodulators. They also secrete novel extracellular enzymes such as amylases, chitinases, cellulases, β-glucanases, inulinases, xylanases and proteases. Nocardiopsis species are aerobic, Gram-positive, non-acid-fast, catalase-positive actinomycetes with nocardioform substrate mycelia and their aerial mycelia bear long chains of spores. Their DNA possesses high contents of guanine and cytosine. There is a marked variation in properties of the isolates obtained from different ecological niches and their products. An important feature of several species is their halophilic or halotolerant nature. They are associated with a variety of marine and terrestrial biological forms wherein they produce antibiotics and toxins that help their hosts in evading pathogens and predators. Two Nocardiopsis species, namely, N. dassonvillei and N. synnemataformans (among the thirty nine reported ones) are opportunistic human pathogens and cause mycetoma, suppurative infections and abscesses. Nocardiopsis species are present in some plants (as endophytes or surface microflora) and their rhizospheres. Here, they are reported to produce enzymes such as α-amylases and antifungal agents that are effective in warding-off plant pathogens. They are prevalent as free-living entities in terrestrial locales, indoor locations, marine ecosystems and hypersaline habitats on account of their salt-, alkali- and desiccation-resistant behavior. In such natural locations, Nocardiopsis species mainly help in recycling organic compounds. Survival under these diverse conditions is mediated by the production of extracellular enzymes, antibiotics, surfactants, and the accumulation of compatible solutes. The accommodative genomic features of Nocardiopsis species support their existence under the diverse conditions where they prevail.
authors.affiliation: Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune 411007, India.
authors.forename: Tahsin
authors.initials: T
authors.lastname: Bennur
authors.affiliation: Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune 411007, India.
authors.forename: Ameeta Ravi
authors.initials: AR
authors.lastname: Kumar
authors.affiliation: Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune 411007, India. Electronic address: smita@unipune.ac.in.
authors.forename: Smita
authors.initials: S
authors.lastname: Zinjarde
authors.affiliation: Department of Biotechnology, Abasaheb Garware College, Pune 411004, India. Electronic address: vaishali.javdekar@mesagc.org.
authors.forename: Vaishali
authors.initials: V
authors.lastname: Javdekar
mesh_terms: D039903:Actinobacteria / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D000220:Adaptation, Biological; D000222:Adaptation, Physiological; D000818:Animals; D017753:Ecosystem; D004783:Environmental Microbiology; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology*; D006801:Humans; D009894:Opportunistic Infections / Q000382:microbiology*; D010944:Plants
keywords: Antibiotics; Enzymes; Marine; Nocardiopsis; Soil