Living strategy of cold-adapted fungi with the reference to several representative species

The male of Cretaconiopteryx grandis Liu & Lu, 2017, which is the only representative species of the extinct dustywing subfamily Cretaconiopteryginae, is described for the first time from the Upper Cretaceous Burmese amber. The male genitalia, well preserved in the examined specimen, show a number of plesiomorphic characters, which support the sister group relationship between Coniopterygidae and the rest of extant lacewing families.

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DFT Benchmark Studies on Representative Species and Poisons of Methane Steam Reforming on Ni(111)

Physical Chemistry Chemical Physics ◽

10.1039/d1cp00862e ◽

2021 ◽

Author(s):

Sai Sharath Yadavalli ◽

Glenn Jones ◽

Michail Stamatakis

Keyword(s):

Steam Reforming ◽

Graphitic Carbon ◽

Methane Steam Reforming ◽

Ni Catalysts ◽

Methane Steam ◽

Representative Species ◽

Industrial Operations ◽

Major Impediment ◽

Carbon Based

Ni catalysts used in Methane Steam Reforming (MSR) are highly susceptible to poisoning by carbon-based species, which poses a major impediment to the productivity of industrial operations. These graphitic carbon-like...

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Molecular cloning and biochemical characterization of a NAD-dependent sorbitol dehydrogenase from cold-adapted Pseudomonas mandelii

FEMS Microbiology Letters ◽

10.1093/femsle/fnaa222 ◽

2021 ◽

Author(s):

Quynh DangThu ◽

Thu-Thuy Nguyen ◽

Sei-Heon Jang ◽

ChangWoo Lee

Keyword(s):

Biochemical Characterization ◽

Size Exclusion ◽

Sorbitol Dehydrogenase ◽

High Catalytic Activity ◽

Active Site Residues ◽

Tertiary Structures ◽

Cold Adapted ◽

Pseudomonas Mandelii ◽

Catalytic Active Site ◽

Exclusion Chromatography

Abstract Sugar alcohols (polyols) have important roles as nutrients, anti-freezing agents, and scavengers of free radicals in cold-adapted bacteria, but the characteristics of polyol dehydrogenases in cold-adapted bacteria remain largely unknown. In this study, based on the observation that a cold-adapted bacterium Pseudomonas mandelii JR-1 predominantly utilized D-sorbitol as its carbon source, among the four polyols examined (D-galactitol, D-mannitol, D-sorbitol, or D-xylitol), we cloned and characterized a sorbitol dehydrogenase (SDH, EC 1.1.1.14) belonging to the short-chain dehydrogenase/reductase family from this bacterium (the SDH hereafter referred to as PmSDH). PmSDH contained Asn111, Ser140, Tyr153, and Lys157 as catalytic active site residues and existed as a ∼67 kDa dimer in size-exclusion chromatography. PmSDH converted D-sorbitol to D-fructose using NAD+ as a coenzyme and, vice versa, D-fructose to D-sorbitol using NADH as a coenzyme. PmSDH maintained its conformational flexibility, secondary and tertiary structures, and thermal stability at 4–25°C. At 40°C, PmSDH was rapidly denatured. These results indicate that PmSDH, which has a flexible structure and a high catalytic activity at colder temperatures, is well-suited to sorbitol utilization in the cold-adapted bacterium P. mandelii JR-1.

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First Speleomycological Study on the Occurrence of Psychrophilic and Psychrotolerant Aeromycota in the Brestovská Cave (Western Tatras Mts., Slovakia) and First Reports for Some Species at Underground Sites

Biology ◽

10.3390/biology10060497 ◽

2021 ◽

Vol 10 (6) ◽

pp. 497

Author(s):

Rafał Ogórek ◽

Mateusz Speruda ◽

Justyna Borzęcka ◽

Agata Piecuch ◽

Magdalena Cal

Keyword(s):

Global Warming ◽

Immune System ◽

Biological Material ◽

Fungal Spores ◽

Airborne Fungi ◽

Fungal Species ◽

Air Samples ◽

Cold Adapted ◽

First Report

Most underground ecosystems are heterotrophic, fungi in these objects are dispersed in the air in the form of spores, and they may be potentially hazardous to mammals. Research in underground sites has focused on mesophilic airborne fungi and only a few concerned cold-adapted species. Therefore, the goal of our research was the first report of psychrophilic and psychrotolerant aeromycota in the Brestovská Cave using culture-based techniques with genetic and phenotypic identification. Plates with PDA medium containing sampled biological material were incubated at 8 ± 0.5 °C. The density of mycobiota inside the cave ranged from 37.4 to 71 CFU 1 m−3 of air and 63.3 CFU 1 m−3 of air outside the cave. Thus, the level of fungal spores did not exceed the standards for the mycological quality of the air. A total of 18 species were isolated during the study, and some species may be potentially dangerous to people with weakened immune system. All fungal species were present inside the cave and only seven of them were outside. Cladosporium cladosporioides dominated in the external air samples and Mortierella parvispora was cultured most frequently from internal air samples. To our knowledge, this is the first discovery of the fungal species such as Coniothyrium pyrinum, Cystobasidium laryngis, Filobasidium wieringae, Leucosporidium drummii, M. parvispora, Mrakia blollopis, Nakazawaea holstii, and Vishniacozyma victoriae in the air inside the underground sites. Moreover, C. pyrinum, C. laryngis, L. drummii, M. blollopis, and N. holstii have never been detected in any component of the underground ecosystems. There are possible reasons explaining the detection of those species, but global warming is the most likely.

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