Marine yeasts—a review

Abstract

Yeasts are ubiquitous in their distribution and populations mainly depend on the type and concentration of organic materials. The distribution of species, as well as their numbers and metabolic characteristics were found to be governed by existing environmental conditions. Marine yeasts were first discovered from the Atlantic Ocean and following this discovery, yeasts were isolated from different sources, viz. seawater, marine deposits, seaweeds, fish, marine mammals and sea birds. Nearshore environments are usually inhabited by tens to thousands of cells per litre of water, whereas low organic surface to deep-sea oceanic regions contain 10 or fewer cells/litre. Aerobic forms are found more in clean waters and fermentative forms in polluted waters. Yeasts are more abundant in silty muds than in sandy sediments. The isolation frequency of yeasts fell as the depth of the sampling site is increased. Major genera isolated in this study were Candida, Cryptococcus, Debaryomyces and Rhodotorula. For biomass estimation ergosterol method was used. Classification and identification of yeasts were performed using different criteria, i.e. morphology, sexual reproduction and physiological/biochemical characteristics. Fatty acid profiling or molecular sequencing of the IGS and ITS regions and 28S gene rDNA ensured accurate identification.

Study on the effects of near-future ocean acidification on marine yeasts: a microcosm approach

“…Discosphaerina (formerly Columnosphaeria) fagi has been suggested as a possible teleomorph, that is, sexual stage, of the black yeast-like fungus Aureobasidium pullulans (Zalar et al 2008), which occurs widespread in the marine environment (Meyers et al 1967). The genera Cryptococcus and Candida are known to contain true marine yeasts (Kutty and Philip 2008) and the species C. sake is present in various aquatic environments including lakes, lagoons, and Antarctic seawater (Boguslawska-Was and Dabrowski 2001;Brandão et al 2011;Buzzini et al 2012). Furthermore, members of this species are pathogens of freshwater prawn, fish, and marine invertebrates (Hatai and Egusa 1975;de Araujo et al 1995;Brilhante et al 2011).…”

“…Yeasts are distinguished from other fungi by their unicellular growth and belong to the phyla Ascomycota or Basidiomycota, respectively (Kutty and Philip 2008). In seawater, their abundances vary from below ten to up to thousands of culturable cells per liter, with highest numbers reported from near-shore and nutrient-rich areas (Fell 2001).…”

“…In seawater, their abundances vary from below ten to up to thousands of culturable cells per liter, with highest numbers reported from near-shore and nutrient-rich areas (Fell 2001). Yeasts play an important role in the breakdown of plant and refractory material and the cycling of nutrients (Meyers and Ahearn 1974;Kutty and Philip 2008) and are frequently found on decaying algae (van Uden and Castelo Branco 1963;Seshadri and Sieburth 1971;Patel 1975). Additionally, yeasts occur associated with marine animals, for example, fish, shrimps, mussels, corals, and seabirds (van Uden and Castelo Branco 1963;Kawakita and van Uden 1965;Ravindran et al 2001;Burgaud et al 2010;Yang et al 2011).…”

Potentially pathogenic yeast isolated from the throat and cloaca of an Arctic colonial seabird: the little auk (Alle alle)

“…Yeasts are a distinctive group of microfungi, growing on organic substrates of many different origins. They are cosmopolitan, occurring in various terrestrial and aquatic habitats, including such extreme environments as deep-sea hydrothermal vents, acidic continental waters, and polar soils (Gadanho and Sampaio 2005;Gadanho et al 2006;Connell et al 2008;Kutty and Philip 2008). The ecological function and biodiversity of yeasts are poorly known.…”

Molecular identification of Pseudozyma aphidis (Henninger & Windisch) Boekhout: first record from a Brazilian mangrove swamp

“…The occurrence and activity of yeasts in marine waters have been observed worldwide since first reported by Fischer & Brebeck (1894) and is well established due to their role in the decomposition of organic substrates, nutrient cycling, hydrocarbon biodegradation, and as pathogenic for a variety of marine organisms (Vogel et al 2007, Kutty & Philip 2008. Species of Pseudozyma, including P. aphidis, have commonly been reported in marine and mangrove environments (Gadanho et al 2003, Statzell-Tallman et al 2010, Fell et al 2011.…”