Antarctic wastewater: A local source of microplastic pollution.

Microplastic (MP) particles can be found all around the planet, even in Antarctica where they can be locally originated or transported by marine currents and winds. In this communication, we identify and report for the first time the contribution of a wastewater treatment plant (WWTP) as a local source of MP particles in the region. The analysis of the entire sample using micro-Raman spectroscopy revealed an MP concentration that ranged from 64 to 159 particles per liter of wastewater.

Deglycosylated RBD produced in Pichia pastoris as a low-cost sera COVID-19 diagnosis tool and a vaccine candidate.

During the COVID-19 outbreak, numerous tools including protein-based vaccines have been developed. The methylotrophic yeast Pichia pastoris (synonymous to Komagataella phaffii) is an eukaryotic cost-effective and scalable system for recombinant protein production, with the advantages of an efficient secretion system and the protein folding assistance of the secretory pathway of eukaryotic cells. In a previous work, we compared the expression of SARS-CoV-2 Spike Receptor Binding Domain in P.

Cyclic heptapeptides with metal binding properties isolated from the fungus Cadophora malorum from Antarctic soil.

The Antarctic fungus Cadophora malorum produces previously undescribed cyclic heptapeptides (cadophorin A and B) containing an anthranilic acid residue. The planar structure of these peptides was determined by high-resolution mass spectrometry combined with extensive 1D and 2D NMR spectroscopy. The absolute configuration of the amino acids was determined by Marfey's method, with HPLC analysis of FDVA (Nα-(2,4-dinitro-5-fluorphenyl)-L-valinamide) derivatives making use of a PFP column.

Microbial associations for bioremediation. What does "microbial consortia" mean?

Microbial associations arise as useful tools in several biotechnological processes. Among them, bioremediation of contaminated environments usually takes advantage of these microbial associations. Despite being frequently used, these associations are indicated using a variety of expressions, showing a lack of consensus by specialists in the field.

Metagenomic strategies identify diverse integron-integrase and antibiotic resistance genes in the Antarctic environment.

The objective of this study is to identify and analyze integrons and antibiotic resistance genes (ARGs) in samples collected from diverse sites in terrestrial Antarctica. Integrons were studied using two independent methods. One involved the construction and analysis of intI gene amplicon libraries.

Bioprospection of cold-adapted yeasts with biotechnological potential from Antarctica.

The aim of this study was to investigate the ability to produce extracellular hydrolytic enzymes at low temperature of yeasts isolated from 25 de Mayo island, Antarctica, and to identify those exhibiting one or more of the evaluated enzymatic activities. A total of 105 yeast isolates were obtained from different samples and 66 were identified. They belonged to 12 basidiomycetous and four ascomycetous genera.

Phenol degradation and heavy metal tolerance of Antarctic yeasts.

In cold environments, biodegradation of organic pollutants and heavy metal bio-conversion requires the activity of cold-adapted or cold-tolerant microorganisms. In this work, the ability to utilize phenol, methanol and n-hexadecane as C source, the tolerance to different heavy metals and growth from 5 to 30 °C were evaluated in cold-adapted yeasts isolated from Antarctica. Fifty-nine percent of the yeasts were classified as psychrotolerant as they could grow in all the range of temperature tested, while the other 41% were classified as psychrophilic as they only grew below 25 °C.

Rich bacterial assemblages from Maritime Antarctica (Potter Cove, South Shetlands) reveal several kinds of endemic and undescribed phylotypes.

Bacterial richness in maritime Antarctica has been poorly described to date. Phylogenetic affiliation of seawater free-living microbial assemblages was studied from three locations near the Argentinean Jubany Station during two Antarctic summers. Sixty 16S RNA cloned sequences were phylogenetically affiliated to Alphaproteobacteria (30/60 clones), Gammaproteobacteria(19/60 clones), Betaproteobacteria and Cytophaga-Flavobacteriia-Bacteroides (CFB), which were (2/60) and (3/60) respectively.

Polyphenolic substrates and dyes degradation by yeasts from 25 de Mayo/King George Island (Antarctica).

Antarctica offers a range of extreme climatic conditions, such as low temperatures, high solar radiation and low nutrient availability, and constitutes one of the harshest environments on Earth. Despite that, it has been successfully colonized by ’cold-loving’ fungi, which play a key role in decomposition cycles in cold ecosystems. However, knowledge about the ecological role of yeasts in nutrient or organic matter recycling/mineralization remains highly fragmentary.

Draft genome sequence of Bizionia argentinensis, isolated from Antarctic surface water.

A psychrotolerant marine bacterial strain, designated JUB59(T), was isolated from Antarctic surface seawater and classified as a new species of the genus Bizionia. Here, we present the first draft genome sequence for this genus, which suggests interesting features such as UV resistance, hydrolytic exoenzymes, and nitrogen metabolism.

Bizionia argentinensis sp. nov., isolated from surface marine water in Antarctica.

A marine bacterial strain, designated strain JUB59(T), was isolated from surface seawater in Antarctica and subsequently characterized. Cells were found to be Gram-negative, non-motile rods forming butyrous, shiny, yellowish orange colonies on marine agar. Growth occurred at 2-28 degrees C (optimally at 22-25 degrees C) but not at 30 degrees C; Na+ ions were required, but 9 % NaCl (w/v) was not tolerated.