Revisiting the pink-red pigmented basidiomycete mirror yeast of the phyllosphere

© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in MicrobiologyOpen 5 (2016): 846–855, doi:10.1002/mbo3.374.By taking advantage of the ballistoconidium-forming capabilities of members of the genus Sporobolomyces, we recovered ten isolates from deciduous tree leaves collected from Vermont and Washington, USA. Analysis of the small subunit ribosomal RNA gene and the D1/D2 domain of the large subunit ribosomal RNA gene indicate that all isolates are closely related. Further analysis of their physiological attributes shows that all were similarly pigmented yeasts capable of growth under aerobic and microaerophilic conditions, all were tolerant of repeated freezing and thawing, minimally tolerant to elevated temperature and desiccation, and capable of growth in liquid or on solid media containing pectin or galacturonic acid. The scientific literature on ballistoconidium-forming yeasts indicates that they are a polyphyletic group. Isolates of Sporobolomyces from two geographically separated sites show almost identical phenotypic and physiological characteristics and a monophyly with a broad group of differently named Sporobolomyces/Sporidiobolus species based on both small subunit ribosomal RNA (SSU rRNA) and D1/D2 domains of the LSU rRNA gene sequences

Multiple environmental parameters impact lipid cyclization in Sulfolobus acidocaldarius

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162708/2/emi15194.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162708/1/emi15194_am.pd

Benthic protists and fungi of Mediterranean deep hypsersaline anoxic basin redoxcline sediments

© The Author(s), 2014. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Frontiers in Microbiology 5 (2014): 605, doi:10.3389/fmicb.2014.00605.Some of the most extreme marine habitats known are the Mediterranean deep hypersaline anoxic basins (DHABs; water depth ∼3500 m). Brines of DHABs are nearly saturated with salt, leading many to suspect they are uninhabitable for eukaryotes. While diverse bacterial and protistan communities are reported from some DHAB water-column haloclines and brines, the existence and activity of benthic DHAB protists have rarely been explored. Here, we report findings regarding protists and fungi recovered from sediments of three DHAB (Discovery, Urania, L’ Atalante) haloclines, and compare these to communities from sediments underlying normoxic waters of typical Mediterranean salinity. Halocline sediments, where the redoxcline impinges the seafloor, were studied from all three DHABs. Microscopic cell counts suggested that halocline sediments supported denser protist populations than those in adjacent control sediments. Pyrosequencing analysis based on ribosomal RNA detected eukaryotic ribotypes in the halocline sediments from each of the three DHABs, most of which were fungi. Sequences affiliated with Ustilaginomycotina Basidiomycota were the most abundant eukaryotic signatures detected. Benthic communities in these DHABs appeared to differ, as expected, due to differing brine chemistries. Microscopy indicated that only a low proportion of protists appeared to bear associated putative symbionts. In a considerable number of cases, when prokaryotes were associated with a protist, DAPI staining did not reveal presence of any nuclei, suggesting that at least some protists were carcasses inhabited by prokaryotic scavengers.K. Kormas was partially supported by the University of Thessaly through a sabbatical in 2013. Supported by NSF grants OCE-0849578 to Virginia P. Edgcomb and Joan M. Bernhard and OCE-1061391 to Joan M. Bernhard and Virginia P. Edgcomb

Protist Community Grazing on Prokaryotic Prey in Deep Ocean Water Masses

Oceanic protist grazing at mesopelagic and bathypelagic depths, and their subsequent effects on trophic links between eukaryotes and prokaryotes, are not well constrained. Recent studies show evidence of higher than expected grazing activity by protists down to mesopelagic depths. This study provides the first exploration of protist grazing in the bathypelagic North Atlantic Deep Water (NADW). Grazing was measured throughout the water column at three stations in the South Atlantic using fluorescently-labeled prey analogues. Grazing in the deep Antarctic Intermediate water (AAIW) and NADW at all three stations removed 3.79% +/- 1.72% to 31.14% +/- 8.24% of the standing prokaryote stock. These results imply that protist grazing may be a significant source of labile organic carbon at certain meso- and bathypelagic depths

Fig 3A: Eukaryote concentrations (#Euks ml^-1) at 0 hours obtained through DAPI stained counts at stations 2, 7 and 23.

<p>Fig 3B: Prokaryote concentrations (# bacteria·mL^-1) obtained through DAPI stained counts at stations 2, 7 and 23. Error bars represent the standard deviation of the mean (n = 2).</p

Temperatures, light levels and sampling times for grazing experiments at stations 2, 7 and 23.

<p>FLP = Fluorescently labeled prey (or prokaryotes).</p><p>Temperatures, light levels and sampling times for grazing experiments at stations 2, 7 and 23.</p

Prokaryote and eukaryote counts and grazing rates reported in the euphotic zone and mesopelagic from different studies.

<p>Prokaryote and eukaryote counts and grazing rates reported in the euphotic zone and mesopelagic from different studies.</p

Fig 4A: Community grazing rates of prokaryotes represented as the number of prokaryotes grazed per day.

<p>Fig 4B: Community grazing rates of prokaryotes as a percentage of prokaryote standing stock grazed. Error bars represent the standard deviation of the mean (n = 2).</p

Water features and metadata (temperature, salinity, dissolved oxygen (DO), total nitrogen (TN), silicate, PO₄ and NPOC (non-purgeable organic carbon), for Stations 2, 7 and 23.

<p>Water features and metadata (temperature, salinity, dissolved oxygen (DO), total nitrogen (TN), silicate, PO₄ and NPOC (non-purgeable organic carbon), for Stations 2, 7 and 23.</p

Temperature (°C), salinity (PSU) and dissolved oxygen (mL· L^-1) depth profiles for stations 2, 7 and 23.

<p>Sampling depths are marked with an asterisk.</p