Step-by-Step Towards Biological Homochirality - from Prebiotic Randomness To Perfect Asymmetry.

The history of life's formation and the origin of its stereochemistry are nearly as multifaceted as the life itself. In this review, we focus on analyzing the step-by-step path leading to what we can define as "life" in parallel to what we know about the emergence of enantiomeric imbalance and subsequent transition to full homochirality. We start at the level of assembly of the building blocks of life from inorganic molecules and build up to the polymerization and formation of nucleic acids and peptides.

Gradual evolution of a homo-l-peptide world on homo-d-configured RNA and DNA.

Modern life requires the translation of genetic information - encoded by nucleic acids - into proteins, which establishes the essential link between genotype and phenotype. During translation, exclusively l-amino acids are loaded onto transfer RNA molecules (tRNA), which are then connected at the ribosome to give homo-l-proteins. In contrast to the homo-l-configuration of amino acids and proteins, the oligonucleotides involved are all d-configured (deoxy)ribosides.

RNA-Templated Peptide Bond Formation Promotes L-Homochirality.

The world in which we live is homochiral. The ribose units that form the backbone of DNA and RNA are all D-configured and the encoded amino acids that comprise the proteins of all living species feature an all-L-configuration at the α-carbon atoms. The homochirality of α-amino acids is essential for folding of the peptides into well-defined and functional 3D structures and the homochirality of D-ribose is crucial for helix formation and base-pairing.

The fungus alters the influence of the endophyte on seed germination and the biomass of grass.

The fungal grass endophyte (Pers.) Tul. & C.

The use of social media in assessing the impact of war on cetaceans.

War has always brought millions of silent non-human victims but the scale of this suffering is often either unknown, neglected or difficult to quantify. Further, the complexities associated with long-term and large-scale monitoring of marine species make it difficult to assess the impacts of war and the mortality of cetaceans resulting from warfare has not been investigated. Here we propose the use of a modified form of citizen science, namely gathering the information from social media.

Loading of Amino Acids onto RNA in a Putative RNA-Peptide World.

RNA is a molecule that can both store genetic information and perform catalytic reactions. This observed dualism places RNA into the limelight of concepts about the origin of life. The RNA world concept argues that life started from self-replicating RNA molecules, which evolved toward increasingly complex structures.

A prebiotically plausible scenario of an RNA-peptide world.

The RNA world concept is one of the most fundamental pillars of the origin of life theory. It predicts that life evolved from increasingly complex self-replicating RNA molecules. The question of how this RNA world then advanced to the next stage, in which proteins became the catalysts of life and RNA reduced its function predominantly to information storage, is one of the most mysterious chicken-and-egg conundrums in evolution.

Contact calls in woodpeckers are individually distinctive, show significant sex differences and enable mate recognition.

Vocal communication of woodpeckers has been relatively little studied so far, mostly because majority of species use drumming to communicate. Our recent study on the Middle Spotted Woodpecker revealed that a call which is specific for floaters is individually distinctive and functions as a vocal signature of unpaired individuals. The aim of the current study is to investigate whether a contact call of paired territory owners of the same species enables discrimination of individuals and their sex.

A New 1,5-Disubstituted Triazole DNA Backbone Mimic with Enhanced Polymerase Compatibility.

Triazole linkages (TLs) are mimics of the phosphodiester bond in oligonucleotides with applications in synthetic biology and biotechnology. Here we report the RuAAC-catalyzed synthesis of a novel 1,5-disubstituted triazole (TL) dinucleoside phosphoramidite as well as its incorporation into oligonucleotides and compare its DNA polymerase replication competency with other TL analogues. We demonstrate that TL has superior replication kinetics to these analogues and is accurately replicated by polymerases.

Equal division of parental care enhances nestling development in the Blackcap.

Because parental care is costly, conflict between mates over their roles in reproduction seems unavoidable unless they both benefit from parental labour split equally between partners. In the current paper we analyse the division of parental investment in the Blackcap (Sylvia atricapilla), a species that experiences high nest predation. We show that both sexes invest in the incubation of eggs as well as feeding and brooding nestlings at a similar level.