<Emphasis Type="Italic">Ogataea phyllophila</Emphasis> sp. nov., <Emphasis Type="Italic">Candida chumphonensis</Emphasis> sp. nov. and <Emphasis Type="Italic">Candida mattranensis</Emphasis> sp. nov., three methylotrophic yeast species from phylloplane in Thailand

Five strains (LN12, LN14^T, LN15^T, LN16 and LN17^T) representing three novel methylotrophic yeast species were isolated from the external surface of plant leaves by three-consecutive enrichments. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and the phylogenetic analysis, the five strains were assigned to be one novel Ogataea species and two novel Candida species. Three strains (LN12, LN14^T and LN16) represent a single novel species of the genus Ogataea, for which the name Ogataea phyllophila sp. nov. is proposed. The type strain is LN14^T (= BCC 42666^T = NBRC 107780^T = CBS 12095^T). Strain LN15^T was assigned to be Candida chumphonensis sp. nov. (type strain LN15^T = BCC 42667^T = NBRC 107781^T = CBS 12096^T). Strain LN17^T represented another novel species of Candida that was named Candida mattranensis sp. nov. (type strain LN17^T = BCC 42668^T = NBRC 107782^T = CBS 12097^T).     

<Emphasis Type="Italic">Candida northwykensis</Emphasis> sp. nov., A Novel Yeast Isolated from the Gut of the Click Beetle <Emphasis Type="Italic">Melanotus villosus</Emphasis>

Two yeast morphotypes, BET 4^T and BET 7, were isolated from the gut of click beetle Melanotus villosus. Click beetles were collected from the decaying timber within the woodlands of North Wyke Research, South West England, UK (latitude, 50°46′29″N; longitude, 3°55′23″W). Morphotype BET 7 was identified as Debaryomyces hansenii, and the other morphotype, BET 4^T, was found to differs from Priceomyces castillae and Priceomyces haplophilus, its closest phylogenetic neighbours, by 5.0% with respect to the nucleotide sequence of the D1/D2 domain of the large-subunit (LSU) rRNA gene, and by 8.0% with respect to the ribosomal internal-transcribed spacer (ITS) region. BET 4^T also differ from P. castillae and P. haplophilus in a number of different phenotypic characteristics. Thus, based on the unique nucleotide sequences of its D1/D2 domain and ITS region, its physiological characteristics and an inability to sporulate, strain BET 4^T is assigned the status of a new species of Candida, for which the name Candida northwykensis sp. nov., is proposed. The type strain is BET 4^T (NCYC 3525^T = CBS 11370^T).     

Susceptibility of <Emphasis Type="Italic">Candida</Emphasis> biofilms to histatin 5 and fluconazole

Candida-associated denture stomatitis has a high rate of recurrence. Candida biofilms formed on denture acrylic are more resistant to antifungals than planktonic yeasts. Histatins, a family of basic peptides secreted by the major salivary glands in humans, especially histatin 5, possess significant antifungal properties. We examined antifungal activities of histatin 5 against planktonic or biofilm Candida albicans and Candida glabrata. Candida biofilms were developed on poly(methyl methacrylate) discs and treated with histatin 5 (0.01–100 μM) or fluconazole (1–200 μM). The metabolic activity of the biofilms was measured by the XTT reduction assay. The fungicidal activity of histatin 5 against planktonic Candida was tested by microdilution plate assay. Biofilm and planktonic C. albicans GDH18, UTR-14 and 6122/06 were highly susceptible to histatin 5, with 50% RMA (concentration of the agent causing 50% reduction in the metabolic activity; biofilm) of 4.6 ± 2.2, 6.9 ± 3.7 and 1.7 ± 1.5 μM, and IC₅₀ (planktonic cells) of 3.0 ± 0.5, 2.6 ± 0.1 and 4.8 ± 0.5, respectively. Biofilms of C. glabrata GDH1407 and 6115/06 were less susceptible to histatin 5, with 50% RMA of 31.2 ± 4.8 and 62.5 ± 0.7 μM, respectively. Planktonic C. glabrata was insensitive to histatin 5 (IC₅₀ > 100 μM). Biofilm-associated Candida was highly resistant to fluconazole in the range 1–200 μM; e.g. at 100 μM only ~20% inhibition was observed for C. albicans, and ~30% inhibition for C. glabrata. These results indicate that histatin 5 exhibits antifungal activity against biofilms of C. albicans and C. glabrata developed on denture acrylic. C. glabrata is significantly less sensitive to histatin 5 than C. albicans.     

<Emphasis Type="Italic">Salinarchaeum laminariae</Emphasis> gen. nov., sp. nov.: a new member of the family <Emphasis Type="Italic">Halobacteriaceae</Emphasis> isolated from salted brown alga <Emphasis Type="Italic">Laminaria</Emphasis>

Halophilic archaeal strains R26^T and R22 were isolated from the brown alga Laminaria produced at Dalian, Liaoning Province, China. Cells from the two strains were pleomorphic rods and Gram negative, and colonies were red pigmented. Strains R26^T and R22 were able to grow at 20–50°C (optimum 37°C) in 1.4–5.1 M NaCl (optimum 3.1–4.3 M) at pH 5.5–9.5 (optimum pH 8.0–8.5) and neither strain required Mg²⁺ for growth. Cells lyse in distilled water and the minimum NaCl concentration required to prevent cell lysis was 8% (w/v) for strain R26^T and 12% (w/v) for strain R22. The major polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and minor phosphatidylglycerol sulfate; glycolipids were not detected. Phylogenetic analyses based on 16S rRNA genes and rpoB′ genes revealed that strains R26^T and R22 formed a distinct clade with the closest relative, Natronoarchaeum mannanilyticum. The DNA G+C content of strains R26^T and R22 was 65.8 and 66.4 mol%, respectively. The DNA–DNA hybridization value between strains R26^T and R22 was 89%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that the strains R26^T and R22 represent a novel species in a new genus within the family Halobacteriaceae, for which the name Salinarchaeum laminariae gen. nov., sp. nov. is proposed. The type strain is R26^T (type strain R26^T = CGMCC 1.10590^T = JCM 17267^T, reference strain R22 = CGMCC 1.10589).     

Four novel <Emphasis Type="Italic">Candida</Emphasis> species in the <Emphasis Type="Italic">Candida albicans</Emphasis>/<Emphasis Type="Italic">Lodderomyces elongisporus</Emphasis> clade isolated from the gut of flower beetles

Flower-visiting beetles belonging to three species of Cetoniidae were collected on three mountains near Beijing, China, and yeasts were isolated from the gut of the insects collected. Based on the 26S rDNA D1/D2 domain and internal transcribed spacer (ITS) region sequence analysis and phenotypic characterization, four novel anamorphic yeast species located in the Candida albicans/Lodderomyces elongisporus clade were identified from 18 of the strains isolated. The new species and type strains are designated as Candida blackwellae AS 2.3639^T (=CBS 10843^T), Candida jiufengensis AS 2.3688^T (=CBS 10846^T), Candida oxycetoniae AS 2.3656^T (=CBS 10844^T), and Candida pseudojiufengensis AS 2.3693^T (=CBS 10847^T). C. blackwellae sp. nov. was basal to the branch formed by C. albicans and C. dubliniensis with moderately strong bootstrap support. The closest relative of C. oxycetoniae was L. elongisporus. C. jiufengensis sp. nov. and C. pseudojiufengensis sp. nov. were closely related with each other and formed a branch in a subclade represented by C. parapsilosis and L. elongisporus.     

<Emphasis Type="Italic">Halomonas qijiaojingensis</Emphasis> sp. nov. and <Emphasis Type="Italic">Halomonas flava</Emphasis> sp. nov., two moderately halophilic bacteria isolated from a salt lake

Two moderately halophilic, Gram-negative, rod-shaped bacteria, designated YIM 93003^T and YIM 94343^T, were isolated from a salt lake in Xinjiang province, north-west China. The two strains YIM 93003^T and YIM 94343^T grew at 20–40°C, pH 6–9, 0.5–24% (w/v) NaCl and at 20–40°C, pH 6–9, 0.5–23% (w/v) NaCl, respectively. No growth occurred in absence of NaCl. Phylogenetic analyses based on 16S rRNA gene sequences showed that strains YIM 93003^T and YIM 94343^T were phylogenetically affiliated to the genus Halomonas and exhibited sequence similarity of 97.5% and 97.4% to the type strain Halomonas anticariensis DSM 16096^T, respectively. The strains possessed chemotaxonomic markers that were consistent with their classification in the genus Halomonas (Q-9 as predominant respiratory quinine; C18:1ω7c, C16:0 and C16:1 ω7c/iso-C15:02-OH as the major fatty acids). The DNA–DNA hybridization values for strains YIM 93003^T and YIM 94343^T, YIM 93003^T and DSM 16096^T, YIM 94343^T and DSM 16096^T were 38.1 ± 3.0, 18.3 ± 4.7, and 20.8 ± 4.6%, respectively. The G+C contents of the strains YIM 93003^T and YIM 94343^T were 63.4 and 64.0 mol%, respectively. Based on comparative analysis of physiological, biochemical and chemotaxonomic data, including low DNA–DNA hybridization results, two novel species, Halomonas qijiaojingensis sp. nov., and Halomonas flava sp. nov., are proposed. The type strains are YIM 93003^T (=CCTCC AB 208133^T =KCTC 22228^T) and YIM 94343^T (=CCTCC AB 2010382^T =KCTC 23356^T), respectively.     

Identification of <Emphasis Type="Italic">Candida</Emphasis> Species Isolated from Bovine Mastitic Milk and Their In Vitro Hemolytic Activity in Western Turkey

In this study, identification of 207 Candida isolates, previously isolated from mastitic bovine quarter milk samples at the level of genus, was made using API 20 C AUX system. The most frequently isolated species were Candida krusei (34.8%), followed by Candida rugosa (16.4%), Candida kefyr (12.6%), Candida albicans (10.1%), and Candida tropicalis (9.2%). Less common isolates were Candida zeylanoides (5.8%), Candida parapsilosis (4.3%), Candida guilliermondii (3.4%), Candida famata (1.9%), and Candida glabrata (1.5%). Additionally, in vitro hemolytic activity of all Candida strains were also examined in the present study. C. krusei (72 isolates), C. kefyr (26), C. albicans (21), C. tropicalis (19), C. zeylanoides (12), and C. glabrata (3) demonstrated both alpha and beta hemolysis at 48-h postinoculation. Only alpha hemolysis was detected in C. rugosa (34), C. guilliermondii (7), and C. famata (4), while C. parapsilosis (9) did not show any hemolytic activity after incubation for 72 h. Statistically significant difference (P < 0.001) was determined between the beta-hemolytic activities of Candida strains. The hemolytic activities of C. zeylanoides, C. albicans and C. kefyr were higher than other strains. This is the first study to describe variable hemolysis types exhibited by different Candida strains isolated from bovine mastitic milk in Turkey.     

<Emphasis Type="Italic">Candida neustonensis</Emphasis> sp. nov., a novel ascomycetous yeast isolated from the sea surface microlayer in Taiwan

A new ascomycetous yeast species, Candida neustonensis is proposed in this study based on four strains (SN92^T, SN47, SJ22, SJ25) isolated from sea surface microlayer in Taiwan. These four yeast strains were morphologically, physiologically and phylogenetically identical to each other. No sexual reproduction was observed on 5% malt extract agar, corn meal agar, V8 agar, McClary’s acetate agar and potato-dextrose agar. Phylogenetic analysis of the sequences of the D1/D2 domain of the large subunit (LSU) rRNA gene places C. neustonensis as a member of the Pichia guilliermondii clade, it also reveals that the phylogenetically closest relatives of C. neustonensis are C. fukuyamaensis (4.4% divergence), C. xestobii (4.4% divergence) and P. guilliermondii (4.5% divergence). C. neustonensis also is clearly distinguished from other known species in the P. guilliermondii clade based on the results of physiology tests. From these comparison analyses, the following novel yeast species is proposed: Candida neustonensis sp. nov., with strain SN92^T (= BCRC 23108^T = JCM 14892^T = CBS 11061^T) as the type strain.     

<Emphasis Type="Italic">Kazachstania intestinalis</Emphasis> sp. nov., an ascosporogenous yeast from the gut of passalid beetle <Emphasis Type="Italic">Odontotaenius disjunctus</Emphasis>

Three ascosporogenous yeast strains were isolated from the gut of the passalid beetle, Odontotaenius disjunctus, inhabiting on rotten oak trees. DNA sequence comparison and other taxonomic characteristics identified the strains as a novel species in the genus Kazachstania. The name Kazachstania intestinalis sp. nov. (type strain EH085^T = ATCC MYA-4658^T = CBS 11839^T) is proposed for the strains. The yeast is homothallic, producing persistent asci with 1–4 spheroidal ascospores. Molecular phylogeny from ribosomal RNA gene sequences placed this novel species on the basal lineage of a clade including Kazachstania lodderae, Kazachstania exigua, Kazachstania martiniae, and other related Kazachstania spp., but none of those species was a close sister to K. intestinalis.     

Evaluation of the Commercial Rapid Trehalose Test (GLABRATA RTT) for the Point of Isolation Identification of <Emphasis Type="Italic">Candida glabrata</Emphasis> Isolates in Primary Cultures

Candidaemias account for 10–20% of nosocomial bloodstream infections depending on the study. Whilst Candida albicans remains the most frequently isolated species, Candida glabrata may be responsible for as many as 10–25% of all candidaemias. Moreover, C. glabrata is generally less susceptible to the azole antifungals than the majority of other pathogenic yeast species. Thus, a rapid test for the specific identification of isolates of C. glabrata would be useful for patient management if it could be performed at point of isolation, on primary cultures grown on standard mycological media directly from patient specimens. Under certain conditions, C. glabrata rapidly hydrolyses trehalose into glucose. The GLABRATA RTT kit allows detection of the preformed enzyme responsible for this action. This study has assessed GLABRATA RTT as an identification tool specifically at point of isolation. Sixty test isolates were evaluated: 39 clinical isolates of C. glabrata identified at the UK Mycology Reference Laboratory, examples of the recently described genetic relatives of C. glabrata, Candida nivariensis (n = 6) and Candida bracarensis (n = 1), and a selection of other common pathogenic yeast species (n = 14). The test provided results within 30 min. Although 77% (30/39) of confirmed C. glabrata isolates were correctly identified by GLABRATA RTT (positive trehalase test), 23% (9/39) of isolates gave negative or equivocal results. All other yeast species gave negative results. The performance of GLABRATA RTT in this study is compared to previous evaluations of the test which employed isolates pre-cultured on specialised media and to other existing conventional identification methodologies.     

<Emphasis Type="Italic">Rhizobium sphaerophysae</Emphasis> sp. nov., a novel species isolated from root nodules of <Emphasis Type="Italic">Sphaerophysa salsula</Emphasis> in China

Four gram-negative, aerobic, motile, non-spore, forming rods with a wide pH and temperature range for growth (pH 7.0–11.0, optimum pH 8.0; 20–45°C, optimum 28°C) strains were isolated from root nodules of Sphaerophysa salsula and characterized by means of a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the four strains formed a new lineage related to the genus Rhizobium and the sequence similarities between the isolate and the most related type strain Rhizobium giardinii was 96.5%. These strains also formed a distinctive group from the reference strains for defined Rhizobium species based on housekeeping gene sequences (atpD and recA), BOX-PCR fingerprinting, phenotypic features and symbiotic properties. The representative strain CCNWGS0238^T has DNA-DNA relatedness of less than 33.4% with the most closely related species R. giardinii. It is therefore proposed as a new species, Rhizobium sphaerophysae sp. nov., with isolate CCNWGS0238^T (=ACCC17498^T = HAMBI3074^T) as the type strain.     

Effect of antifungals on itraconazole resistant <Emphasis Type="Italic">Candida glabrata</Emphasis>

In the last decade, infections caused by Candida glabrata have become more serious, particularly due to its decreased susceptibility to azole derivatives and its ability to form biofilm. Here we studied the resistance profile of 42 C. glabrata clinical isolates to different azoles, amphotericin B and echinocandins. This work was also focused on the ability to form biofilm which plays a role in the development of antifungal resistance. The minimal inhibitory concentration testing to antifungal agents was performed according to the CLSI (Clinical and Laboratory Standards Institute) M27-A3 protocol. Quantification of biofilm was done by XTT reduction assay. All C. glabrata clinical isolates were resistant to itraconazole and sixteen also showed resistance to fluconazole. All isolates remained susceptible to voriconazole. Amphotericin B was efficient in a concentration range of 0.125–1 mg/L. The most effective antifungal agents were micafungin and caspofungin with the MIC₁₀₀ values of ≤0.0313–0.125 mg/L. Low concentrations of these agents reduced biofilm formation as well. Our results show that resistance of different C. glabrata strains is azole specific and therefore a single azole resistance cannot be assumed to indicate general azole resistance. Echinocandins proved to have very high efficacy against clinical C. glabrata strains including those with ability to form biofilm.     

<Emphasis Type="Italic">Saturnispora serradocipensis</Emphasis> sp. nov. and <Emphasis Type="Italic">Saturnispora gosingensis</Emphasis> sp. nov., two ascomycetous yeasts from ephemeral habitats

Two novel ascomycetous yeast species, Saturnispora serradocipensis and Saturnispora gosingensis, were isolated from leaf detritus in a tropical stream of Southeastern Brazil and a mushroom collected in Taiwan, respectively. Analysis of the D1/D2 domains of the large-subunit of the rRNA gene of these strains showed that these species are related to Saturnispora hagleri, their closest relative. Saturnispora serradocipensis and S. gosingensis differed from S. hagleri, respectively, by seven nucleotide substitutions and two indels and three nucleotide substitutions and three indels in D1/D2 rRNA sequences. The two new species differ from each another by four nucleotide substitutions and one indel in D1/D2 rRNA sequences. However, the ITS sequences of S. serradocipensis, S. gosingensis and S. hagleri were quite divergent, showing that they are genetically separate species. The type strain of S. serradocipensis is UFMG-DC-198^T (=CBS 11756^T = NRRL Y-48717^T), and of S. gosingensis GA4M05^T is (CBS 11755^T = NRRL Y-48718^T).     

Use of CHROMagar in the Differentiation of Common Species of <Emphasis Type="Italic">Candida</Emphasis>

CHROMagar has been reported to be useful for the rapid and accurate identification of Candida species. We tested 135 isolates of Candida species isolated from oropharyngeal candidiasis in HIV patients and found that it was useful in the presumptive identification of Candida albicans and Candida krusei. Occasional strains of C. tropicalis produced colonies with a greenish tinge making it difficult to differentiate from C. albicans.     

<Emphasis Type="Italic">Shewanella upenei</Emphasis> sp. nov., a lipolytic bacterium isolated from bensasi goatfish <Emphasis Type="Italic">Upeneus bensasi</Emphasis>

A Gram-staining-negative, motile, non-spore-forming and rod-shaped bacterial strain, 20-23R^T, was isolated from intestine of bensasi goatfish, Upeneus bensasi, and its taxonomic position was investigated by using a polyphasic study. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain 20-23R^T belonged to the genus Shewanella. Strain 20-23R^T exhibited 16S rRNA gene sequence similarity values of 99.5, 99.2, and 97.5% to Shewanella algae ATCC 51192^T, Shewanella haliotis DW01^T, and Shewanella chilikensis JC5^T, respectively. Strain 20-23R^T exhibited 93.1–96.0% 16S rRNA gene sequence similarity to the other Shewanella species. It also exhibited 98.3–98.4% gyrB sequence similarity to the type strains of S. algae and S. haliotis. Strain 20-23R^T contained simultaneously both menaquinones and ubiquinones; the predominant menaquinone was MK-7 and the predominant ubiquinones were Q-8 and Q-7. The fatty acid profiles of strain 20–23R^T, S. algae KCTC 22552^T and S. haliotis KCTC 12896^T were similar; major components were iso-C_15:0, C_16:0, C_16:1 ω7c and/or iso-C_15:0 2-OH and C_17:1 ω8c. The DNA G+C content of strain 20-23R^T was 53.9 mol%. Differential phenotypic properties and genetic distinctiveness of strain 20–23R^T, together with the phylogenetic distinctiveness, revealed that this strain is distinguishable from recognized Shewanella species. On the basis of the data presented, strain 20-23R^T represents a novel species of the genus Shewanella, for which the name Shewanella upenei sp. nov. is proposed. The type strain is 20–23R^T (=KCTC 22806^T =CCUG 58400^T).     

<Emphasis Type="Italic">Singulispaera mucilagenosa</Emphasis> sp. nov., a novel acid-tolerant representative of the order <Emphasis Type="Italic">Planctomycetales</Emphasis>

Two novel strains of budding bacteria, Z-0071^T and Z-0072, were isolated from dystrophic humified waters formed by xylotrophic fungi in the course of spruce wood degradation. The cells of both strains are coccoid (0.95–1.80 μm), nonmotile, single or arranged in pairs. The cells have a complex system of intracellular membranes and are covered with fimbriae and surrounded by a mucous capsule up to 0.3 μm thick. Both strains are aerobic organoheterotrophic, mesophilic, and acid-tolerant microorganisms that are able to grow under microaerobic conditions. They utilize N-acetyl-glucosamine, carbohydrates, and lactate as growth substrates. The strains grow in a pH range of 4.0–7.5 with an optimum at 6.0–6.5. The temperature range for growth is 4–30°C, with an optimum at 25–28°C. Strains Z-0071^T and Z-0072, inhabitants of dystrophic low-mineral waters, are NaCl-sensitive: the NaCl content in the media above 0.5 g/l inhibited growth. The main fatty acids of strains Z-0071^T and Z-0072 are C_16:0, C_18:1ω9c, and C_{18:2ω9c, 12c}. The DNA G + C base content is 51.2–51.7 mol %. The sequences of the 16S rRNA gene fragments (1310 bp) of strains Z-0071^T and Z-0072 were found to be identical. The obtained sequences showed a 94.3% similarity with the sequences of the type strain of the most closely related species Singulisphaera acidiphila MOB10≅T. The phenotypic and phylogenetic properties of strains Z-0071^T and Z-0072 support classification of these strains within the genus Singulisphaera as a new species Singulisphaera mucilagenosa sp. nov., with the type strain Z-0071^T (VKM B-2626).     

<Emphasis Type="Italic">Joostella atrarenae</Emphasis> sp. nov., a novel member of the <Emphasis Type="Italic">Flavobacteriaceae</Emphasis> originating from the black sea sand of Jeju Island

Strain M1-2^T was isolated from the black sand from the seashore of Jeju Island, Republic of Korea and was classified using a polyphasic taxonomic approach. Strain M1-2^T appeared as Gram-negative, motile rods that could grow in the presence of 1–10% (w/v) NaCl and at temperatures ranging from 4 to 37°C. This isolate has catalase and oxidase activity and hydrolyses aesculin, DNA and l-tyrosine. Based on phylogenetic analysis using 16S rRNA gene sequences, strain M1-2^T belongs to the genus Joostella and is clearly distinct from the other described species of this genus, Joostella marina (type strain En5^T). The 16S rRNA gene sequence similarity level between M1-2^T and J. marina En5^T is 97.2%, and the DNA–DNA relatedness value between the two strains is 23.9%. Strain M1-2^T contains MK-6 as the major menaquinone and iso-C_15:0, summed feature 3 (C_16:1 ω7c and/or iso-C_15:0 2OH) and iso-C_17:0 3OH as major cellular fatty acids. The DNA G + C content is 32.3 mol%. These data suggest that strain M1-2^T should be classified as a novel species, for which the name Joostella atrarenae sp. nov. is proposed. The type strain for the novel species is M1-2^T (= KCTC 23194^T = NCAIM B.002413^T).     

<Emphasis Type="Italic">Ogataea saltuana</Emphasis> sp. nov., a novel methanol-assimilating yeast species

Four ascosporulating strains of an undescribed methanol-assimilating yeast species were isolated from forest habitats in Hungary. Three were recovered from rotten wood and one from leaves of a sessile oak (Quercus petraea). An additional isolate of the undescribed species sharing similar phenotypic characters with the above-noted strains was recovered from the gut of an unidentified beetle collected from under the bark of a coniferous tree in Bulgaria. A closely related, but somewhat divergent strain was recovered from insect frass in a Ponderosa pine (Pinus ponderosa) collected in New Mexico, USA. Analysis of the D1/D2 sequences of the LSU rRNA gene placed the new species in the Ogataea clade. The ITS and the D1/D2 LSU sequences of the rRNA gene repeats were compared for the above-noted strains and that of the type strain of Ogataea zsoltii, the closest neighbour among currently recognized Ogataea species. Their relatedness was investigated by parsimony network analysis as well. As a result of the sequence analysis, it was concluded that the six strains isolated from tree associated habitats represent a single new yeast species. Ogataea saltuana sp. nov. is proposed to accommodate these strains. The type strain NCAIM Y.01833^T (CBS 10795^T, NRRL Y-48448^T) was recovered from rotten wood of Scotch pine (Pinus silvestris) in Hungary. The GenBank accession number for the D1/D2 domain nuclear large subunit rRNA gene sequence of strain NCAIM Y.01833^T (CBS 10795^T, NRRL Y-48448^T) is EU327033. The MycoBank number of the new species is MB 519966.     

Response to Oxidative Stress in Eight Pathogenic Yeast Species of the Genus <Emphasis Type="Italic">Candida</Emphasis>

In the course of an infection, the formation of reactive oxygen species by phagocytes and the antioxidant defense mechanisms of microorganisms play a crucial role in pathogenesis. In this study, isolates representing 8 pathogenic Candida species—Candida albicans, Candida dubliniensis, Candida famata, Candida glabrata, Candida guilliermondii, Candida krusei, Candida parapsilosis and Candida tropicalis—were compared with regard to their resistance to oxidative stress in vitro. We evaluated degree of resistance, induction of oxidative damage, capacity to adapt, and induction of antioxidant enzymes. The species showed variable sensitivity to oxidative attack. C. albicans, C. glabrata, and C. krusei were more resistant to oxidative stress under the conditions tested; C. parapsilosis and C. tropicalis presented medium resistance; and C. dubliniensis, C. famata, and C. guilliermondii were more sensitive. The overall greater resistance to oxidative stress of C. albicans and C. glabrata may provide an advantage to these species, which are the major causative agents of candidiasis.