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Femoral glands secrete a wax-like substance on the inner side of lizard hind legs, which is thought to function as a mode of chemical communication. Though the minor volatile fraction is well studied, the major protein fraction remains enigmatic. Here, we use proteomics to analyze proteins in femoral gland secretions of the Galápagos marine iguana. Although we found no evidence for proteins and peptides involved in chemical communication, we found several immune-regulatory proteins which also demonstrate anti-microbial functions. Accordingly, we show that femoral gland proteins and peptides function as a barrier against microbial infection and may prevent the rapid degradation of volatile substances., Graphical Abstract Highlights • Comprehensive transcriptome and proteome of the Galápagos Marine Iguana. • Analysis of femoral gland proteome. • Identification of antimicrobial activity in femoral gland secretions., Communication between individuals via molecules, termed chemosignaling, is widespread among animal and plant species. However, we lack knowledge on the specific functions of the substances involved for most systems. The femoral gland is an organ that secretes a waxy substance involved in chemical communication in lizards. Although the lipids and volatile substances secreted by the femoral glands have been investigated in several biochemical studies, the protein composition and functions of secretions remain completely unknown. Applying a proteomic approach, we provide the first attempt to comprehensively characterize the protein composition of femoral gland secretions from the Galápagos marine iguana. Using samples from several organs, the marine iguana proteome was assembled by next-generation sequencing and MS, resulting in 7513 proteins. Of these, 4305 proteins were present in the femoral gland, including keratins, small serum proteins, and fatty acid-binding proteins. Surprisingly, no proteins with discernible roles in partner recognition or inter-species communication could be identified. However, we did find several proteins with direct associations to the innate immune system, including lysozyme C, antileukoproteinase (ALP), pulmonary surfactant protein (SFTPD), and galectin (LGALS1) suggesting that the femoral glands function as an important barrier to infection. Furthermore, we report several novel anti-microbial peptides from the femoral glands that show similar action against Escherichia coli and Bacillus subtilis such as oncocin, a peptide known for its effectiveness against Gram-negative pathogens. This proteomics data set is a valuable resource for future functional protein analysis and demonstrates that femoral gland secretions also perform functions of the innate immune system.

The outbreak of the new Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a public health emergency. Asthma does not represent a risk factor for COVID-19 in several published cohorts. We hypothesized that the SARS-CoV-2 proteome contains T cell epitopes, which are potentially cross-reactive to allergen epitopes. We aimed at identifying homologous peptide sequences by means of two distinct complementary bioinformatics approaches. Pipeline 1 included prediction of MHC Class I and Class II epitopes contained in the SARS-CoV-2 proteome and allergens along with alignment and elaborate ranking approaches. Pipeline 2 involved alignment of SARS-CoV-2 overlapping peptides with known allergen-derived T cell epitopes. Our results indicate a large number of MHC Class I epitope pairs including known as well as de novo predicted allergen T cell epitopes with high probability for cross-reactivity. Allergen sources, such as Aspergillus fumigatus, Phleum pratense and Dermatophagoides species are of particular interest due to their association with multiple cross-reactive candidate peptides, independently of the applied bioinformatic approach. In contrast, peptides derived from food allergens, as well as MHC class II epitopes did not achieve high in silico ranking and were therefore not further investigated. Our findings warrant further experimental confirmation along with examination of the functional importance of such cross-reactive responses.

We report here a complete genome sequence of Ebola virus Makona from a nonfatal patient sample that originated in Sierra Leone during the last Ebola virus outbreak in West Africa (species Zaire ebolavirus ) using a highly accurate circle sequencing (Cir-seq) method.

We report the use of antimicrobial hemolymph proteins from the model host Galleria mellonella as an inhibitor for various Listeria strains, providing a novel source for antilisterial therapeutics. We also have shown that specific virulence-associated genes known to mediate antimicrobial resistance of Listeria in mammalian models indicated a similar function in Galleria .

In the recent years, the number of drug- and multi-drug-resistant microbial strains has increased rapidly. Therefore, the need to identify innovative approaches for development of novel anti-infectives and new therapeutic targets is of high priority in global health care. The detection of small RNAs (sRNAs) in bacteria has attracted considerable attention as an emerging class of new gene expression regulators. Several experimental technologies to predict sRNA have been established for the Gram-negative model organism Escherichia coli. In many respects, sRNA screens in this model system have set a blueprint for the global and functional identification of sRNAs for Gram-positive microbes, but the functional role of sRNAs in colonization and pathogenicity for Listeria monocytogenes, Staphylococcus aureus, Streptococcus pyogenes, Enterococcus faecalis and Clostridium difficile is almost completely unknown. Here, we report the current knowledge about the sRNAs of these socioeconomically relevant Gram-positive pathogens, overview the state-of-the-art high-throughput sRNA screening methods and summarize bioinformatics approaches for genome-wide sRNA identification and target prediction. Finally, we discuss the use of modified peptide nucleic acids (PNAs) as a novel tool to inactivate potential sRNA and their applications in rapid and specific detection of pathogenic bacteria.

Devosia sp. nov. DDB001, isolated from mycotoxin-contaminated soil, is a potential mycotoxin-degrading alphaproteobacterium. To our knowledge, this is the first draft genome announcement of a Devosia species.

We have investigated desorption and dissociation of O2 chemisorbed on Ag(001) induced by collision with hyperthermal Xe and Ar atoms by high resolution electron energy loss spectroscopy and supersonic molecular beam technique. The cross section for both processes increases rapidly both as a function of angle of incidence and of total impact energy of the inert gas atom. While the increase with energy is expected, the increase with the angle is somewhat surprising and is sensibly larger than observed for previously investigated systems. The cross section for desorption decreases moreover with coverage. In the limit of high impact energy and high coverage its value is always larger than the one for dissociation. The branching ratio between the two processes depends thereby on energy and angle of incidence of the inert gas atom. Atomic oxygen is not removed under any impact condition, because of its larger binding energy. In order to explain the experimental results, molecular dynamics simulations have been ...

Physisorbed O2 on Ag(111) at mono- and multilayer coverages was studied by high-resolution electron energy-loss spectroscopy. As the excitation mechanism, the 4∑−u negative-ion resonance was chosen. The O2 stretch mode and its overtones exhibit a strong tail to higher loss energies. For the multilayer, a broad peak around 7 meV is observed. This observation and the lack of any larger intensity on the gain side made it likely that vibrational energy quanta as large as 7 meV are the dominant contribution to the tail.

For benzene chemisorbed on Pt(111) a negative ion resonance has been found at 2.1 eV above the vacuum energy. The resonance is assigned to the b 2g (π∗) orbital of benzene. The shift of its energy upon adsorption is discussed in the light of the chemical bonding of the molecule to the surface.

The interactions of satd. layers of molecularly adsorbed O₂ on Pd(111) with post-dosed CO have been studied with temp. programmed desorption (TPD) and electron energy loss spectroscopy (EELS) in the surface temp. range 100-230 K. It has been found that CO does not react chem. with O₂(a) to form CO₂. CO does react with adsorbed O atoms at higher surfaces temps. resulting in the prodn. of CO2. Introducing CO to a satd. O₂ layer decreases the total O₂(a) coverage as well as changing the relative populations of the three chemisorbed O₂ species.

We have performed extensive HREELS studies on the O2/Pd(111) chemisorption system. The aim of these investigations is to identify and characterize negative ion resonances in inelastic electron scattering by molecular oxygen adsorbed on palladium. Such resonances have been suggested to play an important role in the photochemistry of this system. The O2/Pd(111) system is of particular interest because three different chemisorbed states are known to exist and its photochemistry has been well characterized. We have found a pronounced resonance feature at ∼ 1 eV and discuss the dependence of the scattered electron intensity as a function of both primary electron energy and final scattering angle in terms of the structure of this resonance.

The system O₂/Pd (111) was probed with EELS and thermal desorption spectrometry. The coincidence of 3 peaks in thermal desorption and the O-O region of the EELS spectrum was noted previously and a one-to-one correspondence between the states resolved in EELS and the desorption features was assumed. The authors show that this assumption is incorrect. The lowest binding energy state correlates with the highest frequency vibrational state. The lowest vibrational frequency state acts as a precursor to dissocn. The 2 higher temp. thermal desorption features both arise from the remaining state.

This article gathers together a collection of recent experimental studies of the adsorption of oxygen on (001), (110) and (111) crystal surfaces of silver with special emphasis on the negative ion states of this model system for oxygen adsorption. These investigations were performed in a network entitled `Negative ion resonances of adsorbed molecules' supported financially by the European Union within the `Human capital and mobility programme'. The kinetics and thermodynamics of adsorption are investigated by measuring the sticking coefficient and by thermal desorption spectroscopy (TDS). The vibrational spectra provided by high-resolution electron energy loss spectroscopy (HREELS) are used to analyse the adsorbed species (physisorbed and chemisorbed) in the case of O2 on Ag(110) and on Ag(111). The mechanisms of inelastic electron scattering by adsorbed O2 are further investigated with special reference to the negative ion resonances (NIRs), formed by electron capture, which are involved in the electron-molecule collision process.

Ozone (${\mathrm{O}}_{3}$) was synthesized in the condensed phase induced by electron bombardment of multilayer films of molecular oxygen condensed at temperatures below 30 K on metal surfaces. ${\mathrm{O}}_{3}$ formation was demonstrated by the observation of the asymmetric stretching ( ${\ensuremath{\nu}}_{3}$) and bending ( ${\ensuremath{\nu}}_{2}$) normal modes of vibration in a high-resolution electron energy-loss spectroscopy experiment, and by characteristic changes in electron-stimulated desorption of ${\mathrm{O}}^{\ensuremath{-}}$. The threshold electron energy for the ${\mathrm{O}}_{3}$ formation is found at $3.5\ifmmode\pm\else\textpm\fi{}0.2\mathrm{eV}$. It corresponds to the formation of O${(}^{3}$P) associated with ${\mathrm{O}}^{\ensuremath{-}}(^{2}P)$ by dissociative electron attachment at condensed ${\mathrm{O}}_{2}$, followed by the third body reaction $\mathrm{O}+{\mathrm{O}}_{2}+{\mathrm{O}}_{2}\ensuremath{\rightarrow}{\mathrm{O}}_{3}+{\mathrm{O}}_{2}$. Above 5.1 eV bombarding energy, dissociative excitation of the ${\mathrm{O}}_{2}^{*}$ ( ${c}^{1}{\ensuremath{\Sigma}}_{u}^{\ensuremath{-}}{,C}^{3}{\ensuremath{\Delta}}_{u}{,A}^{3}{\ensuremath{\Sigma}}_{u}^{+}{,B}^{3}{\ensuremath{\Sigma}}_{u}^{\ensuremath{-}}$) states is the main source of atomic oxygen O${(}^{3}$P) or O${(}^{1}$D) involved in the ${\mathrm{O}}_{3}$ synthesis.

High resolution electron energy loss spectroscopy (HREELS) has been used to locate a negative ion resonance at about 2.1 eV electron beam energy in benzene chemisorbed on Pt(111). We determine the predominant excitation mechanisms for several vibrational modes of the adsorbate. A group theoretical analysis of the resonantly excited modes is used to deduce the symmetry of the adsorbate complex. Emphasis is laid on the influence of the vibronic coupling to neighbouring resonances. We come to the conclusion that the symmetry of the adsorbate complex should be either C3v(σv) or Cs(σv).

We have investigated desorption and dissociation of O2 chemisorbed on Ag(001) induced by collision with hyperthermal Xe and Ar atoms provided by a supersonic molecular beam. We find that the cross section for both processes increases rapidly with impact energy and with angle of incidence of the inert gas atom. A model is presented which accounts for the observed energy threshold and for the trend in the cross section.