Yarrowia divulgata f.a., sp. nov., a yeast species from animal-related and marine sources Five yeast strains, phenotypically indistinguishable from Yarrowia lipolytica and Yarrowia deformans, were recovered from different animal-related samples. One strain was isolated from a bacon processing plant in Denmark, two strains from chicken liver in the USA, one strain from chicken breast in Hungary and one from minced beef in Hungary. Comparisons of the sequences of their large subunit rRNA gene D1/D2 domain and the internal transcribed spacer (ITS) regions revealed that, despite their phenotypic similarity, they represent a novel yeast species of the Yarrowia clade with Y. deformans being the genotypically closest relative (LSU rRNA gene D1/D2 and ITS region similarity of 97.0 and 93.7 %, respectively). Yarrowia divulgata f.a., sp. nov. is proposed to accommodate these strains with F6-17 T (5CBS 11013 T 5CCUG 56725 T ) as the type strain. Some D1/D2 sequences of yeasts from marine habitats were found in the GenBank database that were identical to those of the strains of Y. divulgata f.a., sp. nov. Unfortunately, these strains were not available for our study.Yarrowia lipolytica is a widely reported contaminant of mainly dairy and meat products (Kurtzman, 2011) where it is a common yeast contaminant and spoilage organism (e.g. Ismail et al., 2000; Vasdinyei & Deák, 2003;Mayoral et al., 2005; Deák, 2008). However, in some cases Y. lipolytica also plays a beneficial role in the food industry such as in some fermented sausages (Encinas et al., 2000) and Raclette cheese where it positively influences flavour (Wyder et al., 1999). Furthermore, it is potentially useful for the production of citric acid (Mirbagheri et al., 2012). Groenewald et al. (2013) summarized information on the current and potential industrial applications of Y. lipolytica, as well as information on its safety. Based on their review, they concluded that Y. lipolytica is 'safe-to-use' in feed or food, or when deployed as a production host for biotechnological applications.Y. lipolytica remained the only known member of the genus for a long time. However, based on D1/D2 sequence comparisons (Bigey et al., 2003) and a polyphasic approach (Knutsen et al., 2007) the heterogeneity of the species was recognized and the reinstatement of Candida deformans, one of its synonyms, was proposed. In the last decade, descriptions of numerous novel species belonging to the Yarrowia clade have been enabled by molecular biology methods such as sequence analysis (Péter et al., 2004;Kurtzman, 2005;Knutsen et al., 2007;Limtong et al., 2008;Groenewald & Smith, 2013). At the time of writing, ten recognized species are assigned to the Yarrowia clade (Limtong et al., 2008;Kurtzman, 2011;Lachance et al., 2011;Groenewald & Smith, 2013). In the present paper, we report the isolation of five yeast strains from different animal-related sources. These strains form a group in the Yarrowia clade, characterized by identical D1/D2 and ITS sequences that are sufficiently different from...

Eleven yeast strains representing two hitherto undescribed species were isolated from different kinds of meat samples in Hungary and one from the sediment of a tropical freshwater river in Southeastern Brazil. The analysis of the sequences of their large subunit rRNA gene D1/D2 domain and the internal transcribed spacer (ITS) regions placed the two new species in the Yarrowia clade. Some of the seven strains representing the first new species can mate and give rise to asci and form ascospores embedded in capsular material, which qualifies it as the third teleomorph species of the Yarrowia clade. The name Yarrowia porcina sp. nov. (type strain: NCAIM Y.02100(T) = CBS 12935(T) = NRRL Y-63669(T), allotype strain UFMG-RD131(A) = CBS 12932(A)) is proposed for this new yeast species, which, based on physiological characters, is indistinguishable from Yarrowia lipolytica and some other species of the genus. Considerable intraspecific variability was detected among the sequences of the large subunit rRNA gene D1/D2 domains of the seven strains. The variability among the D1/D2 sequences exceeded the divergence observed among the ITS sequences and in some cases more than 1 % substitution among the D1/D2 sequences was detected. The conspecificity of these strains was supported by the low (0-3 substitutions) sequence divergence among their ITS sequences, the result of a parsimony network analysis utilizing the concatenated ITS and D1/D2 sequences and also by the fingerprint patterns generated by microsatellite primed PCR. No ascospore formation was observed in the group of the other five strains representing the second new species. These strains shared identical D1/D2 and ITS sequences. Yarrowia bubula f.a., sp. nov. (type strain: NCAIM Y.01998(T) = CBS 12934(T) = NRRL Y-63668(T)) is proposed to accommodate these strains.

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Yeasts of the Yarrowia clade frequently occur in meat and milk products. In many cases they cause spoilage due to their strong lipolytic and proteolytic activity, and their ability to produce brown pigments. Using conventional methods, some of these yeasts can be misidentifi ed as Yarrowia lipolytica, but using molecular biological methods it can be stated that they are members of a complex group including several different species. The aims of this study were to fi nd a proper method to collect Yarrowia strains from raw meat, and to assign them to groups based on their physiological and molecular characteristics, followed by sequence-based identifi cation of the selected members of each group to determine the composition of the species. This study revealed three novel Yarrowia species. From 62 samples of different raw meats 291 yeast strains were isolated, from which 118 strains proved to be members of the Yarrowia group. They could be assigned to seven species. Four of them are described species, three of them are novel ones.

Yarrowia lipolytica is a frequently reported food spoilage yeast which occurs mainly in meat and milk products. Besides its detrimental role in the food spoilage it has many favourable properties. This yeast also has been developed as a production host for a large variety of biotechnological applications. Some species of the Yarrowia group cannot be differentiated by conventional methods based on phenotypic characteristics, so it is probable that not only Yarrowia lipolytica, but also other species of the Yarrowia group contribute to food spoilage or can have a beneficial role in the industry. A relatively fast, easy and low-cost but reliable method would be useful to differentiate and identify these species properly. Microsatellite PCR fingerprinting method is commonly used for the discrimination of species or strains within species, it is also applied for the identification of yeast species and in many yeast diversity studies, however, its reliability can be queried. The aim of this study was to assess the reliability of microsatellite PCR fingerprinting using (GAC)5 primer in the differentiation and identification of the yeast strains of the Yarrowia group by clustering them using microsatellite-PCR fingerprinting, then identifying them by sequencing the D1/D2 regions of the LSU rDNA of one or a few selected representatives of each cluster. Two hundred and nineteen yeast strains of the Yarrowia group were examined. Using this molecular biological method, yeast strains of the Yarrowia group from raw meat, raw milk, cheese and cottage cheese were assigned to seven species The food spoilage yeast strains of the Yarrowia group can be successfully differentiated by using microsatellite PCR fingerprinting method using (GAC)5 primer, even their identity, thus their diversity can be assessed.