4 research outputs found
High-level diversity of tailed phages, eukaryote-associated viruses, and virophage-like elements in the metaviromes of Antarctic soils
The metaviromes of two distinct Antarctic hyperarid desert soil communities have been characterized. Hypolithic communities,
cyanobacterium-dominated assemblages situated on the ventral surfaces of quartz pebbles embedded in the desert pavement,
showed higher virus diversity than surface soils, which correlated with previous bacterial community studies. Prokaryotic viruses
(i.e., phages) represented the largest viral component (particularly Mycobacterium phages) in both habitats, with an identical
hierarchical sequence abundance of families of tailed phages (Siphoviridae>Myoviridae>Podoviridae). No archaeal viruses
were found. Unexpectedly, cyanophages were poorly represented in both metaviromes and were phylogenetically distant from
currently characterized cyanophages. Putative phage genomes were assembled and showed a high level of unaffiliated genes,
mostly from hypolithic viruses. Moreover, unusual gene arrangements in which eukaryotic and prokaryotic virus-derived genes
were found within identical genome segments were observed. Phycodnaviridae and Mimiviridae viruses were the second-mostabundant
taxa and more numerous within open soil. Novel virophage-like sequences (within the Sputnik clade) were identified.
These findings highlight high-level virus diversity and novel species discovery potential within Antarctic hyperarid soils and may
serve as a starting point for future studies targeting specific viral groups.IS
Niche-dependent genetic diversity in Antarctic metaviromes
The metaviromes from 2 different
Antarctic terrestrial soil niches have
been analyzed. Both hypoliths (microbial
assemblages beneath transluscent rocks)
and surrounding open soils showed a
high level diversity of tailed phages,
viruses of algae and amoeba, and virophage
sequences. Comparisons of other
global metaviromes with the Antarctic
libraries showed a niche-dependent clustering
pattern, unrelated to the geographical
origin of a given metavirome. Within
the Antarctic open soil metavirome, a
putative circularly permuted, »42kb
dsDNA virus genome was annotated,
showing features of a temperate phage
possessing a variety of conserved protein
domains with no significant taxonomic
affiliations in current databases.National Research Foundation (South Africa) and the Genomics Research Institute of the
University of Pretoria (South Africa).http://www.tandfonline.com/loi/kbac202015-12-31hb201
ISSN exercise & sport nutrition review: research & recommendations
Sports nutrition is a constantly evolving field with hundreds of research papers published annually. For this reason, keeping up to date with the literature is often difficult. This paper is a five year update of the sports nutrition review article published as the lead paper to launch the JISSN in 2004 and presents a well-referenced overview of the current state of the science related to how to optimize training and athletic performance through nutrition. More specifically, this paper provides an overview of: 1.) The definitional category of ergogenic aids and dietary supplements; 2.) How dietary supplements are legally regulated; 3.) How to evaluate the scientific merit of nutritional supplements; 4.) General nutritional strategies to optimize performance and enhance recovery; and, 5.) An overview of our current understanding of the ergogenic value of nutrition and dietary supplementation in regards to weight gain, weight loss, and performance enhancement. Our hope is that ISSN members and individuals interested in sports nutrition find this review useful in their daily practice and consultation with their clients