Four new species of Metschnikowia and the transfer of seven Candida species to Metschnikowia and Clavispora as new combinations

Abstract

From comparisons of ITS1-5.8S-ITS2 and gene sequences for nuclear D1/D2 LSU rRNA, nuclear SSU (18S) rRNA, translation elongation factor 1-α (EF1-α) and RNA polymerase II subunit 2 (RPB2), the following four new ascosporogenous yeast species were resolved and are described as Metschnikowia anglica (NRRL Y-7298 [type strain], CBS 15342, MycoBank MB 823167), Metschnikowia leonuri (NRRL Y-6546, CBS 15341, MB 823166), Metschnikowia peoriensis (NRRL Y-5942, CBS 15345, MB 823164) and Metschnikowia rubicola (NRRL Y-6064, CBS 15344, MB 823165). The following six species of Candida are members of the Metschnikowia clade and are proposed for transfer to Metschnikowia as new combinations: Candida chrysomelidarum (NRRL Y-27749, CBS 9904, MB 823223), Candida gelsemii (NRRL Y-48212, CBS 10509, MB 823192), Candida kofuensis (NRRL Y-27226, CBS 8058, MB 823195), Candida picachoensis (NRRL Y-27607, CBS 9804, MB 823197), Candida pimensis (NRRL Y-27619, CBS 9805, MB 823205) and Candida rancensis (NRRL Y-48702, CBS 8174, MB 823224). Candida fructus (NRRL Y-17072, CBS 6380, MB 823206) is transferred to Clavispora as a new combination, and Candida musae is shown to be a synonym of C. fructus. Apparent multiple alleles for ITS, D1/D2, EF1-α and RPB2 were detected in strains of some species.

Metschnikowia pulcherrima and Related Pulcherrimin-Producing Yeasts: Fuzzy Species Boundaries and Complex Antimicrobial Antagonism

“…Pulcherrimin-producing Metschnikowia strains are common components of the yeast communities that colonise ripening fruits, flowers (nectar), tree sap fluxes and also frequently occur in fruit juices and fermenting wine (e.g., [ 2 , 3 , 6 , 9 , 12 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ]). New yeast isolates producing the characteristic maroon-red pulcherrimin halos around their colonies ( Figure 1 A) are frequently declared to belong to M. pulcherrima without taking into account that M. pulcherrima is not the only pigment-producing Metschnikowia species.…”

“…The intensity of pigment production is variable and highly dependent on the culturing conditions [ 6 , 33 , 34 ] and probably also on ploidy [ 35 ]. The phylogenetic analysis of the barcode sequences of the type strains of the genus clustered these species in a group designated M. pulcherrima clade [ 1 , 2 ].…”

“…This method widely used in yeast taxonomy turned out to have limited applicability in the pulcherrimin-producing Metschnikowia yeasts because the amplified D1/D2 domains and ITS segments frequently have ambiguous nucleotides (e.g., [ 2 , 5 , 12 , 18 , 20 , 46 , 47 , 48 ]). It is unknown how widespread the phenomenon is because the ambiguous nucleotides are usually considered sequencing errors to be eliminated from the nascent sequences before the sequence is deposited in a database.…”

“…2020) but the number or species is continuously growing. The M. pulcherrima clade of the genus contains seven validly described species that share the ability to produce pulcherrimin, a maroon-red pigment (reviewed in [ 1 , 2 ]). These species and the strains closely related to them have broad biotechnological potential for application in various industrial processes.…”

The yeast community of Conotelus sp. (Coleoptera: Nitidulidae) in Brazilian passionfruit flowers (Passiflora edulis) and description of Metschnikowia amazonensis sp. nov., a large‐spored clade yeast

“…On the basis of its unusual morphology, featuring a long, flexuous ascus containing a single, thin, belaying pin‐shaped ascospore, M etschnikowia cauda ta has been conjectured (Lachance, ) not to be a genuine Metschnikowia species. Kurtzman, Robnett, Basehoar, and Ward () suggested a moderate affinity with Metschnikowia drosophilae and Metschnikowia torresii but did not believe that the large‐spored clade, exclusive of Metschnikowia hawaiiana and M etschnikowia orientali s , should be retained in the genus. The phylogeny in Figure clearly identifies M. hawaiiana and M. orientalis as a sister clade to the large‐spored clade as previously understood, and the homogeneity of their a pheromones (Lee et al, ) strongly argues for inclusion of the two species in the large‐spored clade, as done in Figure .…”