Although vaccines confer protection against influenza A viruses, antiviral treatment becomes the first line of defense during pandemics because there is insufficient time to produce vaccines. Current antiviral drugs are susceptible to drug resistance, and developing new antivirals is essential. We studied host defense peptides from the skin of the South Indian frog and demonstrated that one of these, which we named "urumin," is virucidal for H1 hemagglutinin-bearing human influenza A viruses. This peptide specifically targeted the conserved stalk region of H1 hemagglutinin and was effective against drug-resistant H1 influenza viruses. Using electron microscopy, we showed that this peptide physically destroyed influenza virions. It also protected naive mice from lethal influenza infection. Urumin represents a unique class of anti-influenza virucide that specifically targets the hemagglutinin stalk region, similar to targeting of antibodies induced by universal influenza vaccines. Urumin therefore has the potential to contribute to first-line anti-viral treatments during influenza outbreaks.

This paper documents the occurrence of the exotic South American suckermouth armoured catfishes (Loricariidae) of the genus Pterygoplichthys spp. in the drainages of Thiruvananthapuram City, Kerala. The morphological taxonomy revealed that the specimens are closely related to Pterygoplichthys disjunctivus (Weber, 1991) and P. pardalis (Castelnau, 1855), in addition to intermediary forms of unknown identity. DNA barcoding using the mitochondrial DNA cytochrome c oxidase 1 (CO1) also failed to establish the identity of the invaded species. There may be possible hybridisation in aquariums or in fish farms or in the wild, but this needs to be found out aided by detailed studies incorporating different molecular markers and with sequences of topotypes. The possible threats due to Pterygoplichthys spp. invasion and management options are discussed in the paper.

Amphibians are rapidly declining worldwide, but recent studies have shown that their diversity may be heavily underestimated, and many new species have been recently reported from biodiversity hotspots. For successful conservation and management strategies to be implemented within such hotspots, a better understanding of the species diversity and their evolutionary relationships is required. We used three mitochondrial (16S, 12S and CO1) and two nuclear (rag1 and rhodopsin) gene fragments to investigate the genetic diversity within the endemic Indirana genus from the Western Ghats biodiversity hotspot. The species diversity within Indirana was found to be much higher than previously anticipated. Instead of the expected six species within this region, our analyses identified 11 clades with high (4.2-17.1%) sequence divergence. Each of these clades is likely to represent a distinct species. Particularly pronounced polyphyly was found within Indirana beddomii, which consisted of four highly supported monophyletic clades with high genetic divergence. Similarly, Indirana diplosticta was divided into two highly divergent monophyletic clades. We also report a new candidate species within the genus from Vellarimala in Kerala, which we believe is yet to be described. Our results suggest the existence of multiple unrecognized cryptic lineages within Indirana, all of which are likely to have more narrow distribution ranges and lower abundances than the taxonomic units into which they are currently assigned. Hence, the International Union for Conservation of Nature (IUCN) Red List statuses of Indirana frogs are likely to be in need of substantial revision, and detailed genetic studies across the Western Ghats might uncover additional new candidate species from this poorly studied endemic genus. Together with several earlier amphibian studies describing cryptic species from tropics, our results highlight the importance of proper species identification efforts before it is possible to reliably determine the IUCN conservation status of tropical amphibians described on the basis of morphological criteria. bs_bs_banner Animal Conservation. Print ISSN 1367-9430 Animal Conservation 15 (2012) 489-498

All life forms are equipped with rapidly acting, evolutionally conserved components of an innate immune defense system that consists of a group of unique and diverse molecules known as host defense peptides (HDPs). A Systematic and Modular Modification and Deletion (SMMD) approach was followed to analyse the structural requirement of B1CTcu5, a brevinin antibacterial peptide amide identified from the skin secretion of frog Clinotarsus curtipes, India, to show antibacterial activity and to explore the active core region. Seventeen SMMD-B1CTcu5 analogs were designed and synthesised by C and N-terminal amino acid substitution or deletion. Enhancement in cationicity by N-terminal Lys/Arg substitution or hydrophobicity by Trp substitution produced no drastic change in bactericidal nature against selected bacterial strains except S. aureus. But the sequential removal of N-terminal amino acids had a negative effect on bactericidal potency. Analog B1CTcu5-LIAG obtained by the removal of four N-terminal amino acids displayed bactericidal effect comparable to, or in excess of, the parent peptide with reduced hemolytic character. Its higher activity was well correlated with the improved inner membrane permeabilisation capacity. This region may act as the active core of B1CTcu5. Presence of C-terminal disulphide bond was not a necessary condition to display antibacterial activity but helped to promote hemolytic nature. Removal of the C-terminal rana box region drastically reduced antibacterial and hemolytic activity of the peptide, showing that this region is important for membrane targeting. The bactericidal potency of the D-peptide (DB1CTcu5) helped to rule out the stereospecific interaction with the bacterial membrane. Our data suggests that both the C and N-terminal regions are necessary for bactericidal activity, even though the active core region is located near the N-terminal of B1CTcu5. A judicious modification at the N-terminal region may produce a short SMMD analog with enhanced bactericidal activity and low toxicity against eukaryotic cells.

Chronic diabetic foot is a global burden affecting millions of people, and the chronicity of an ulcer is directly linked to the diverse bacterial burden and its biofilm mode of infection. The bacterial diversity of 100 chronic diabetic ulcer samples was profiled via traditional culturing method as well as metagenomic approach by sequencing the 16S rRNA V3 hyper-variable region on Illumina Miseq Platform (Illumina, Inc., San Diego, CA). All the relevant clinical metadata, including duration of diabetes, grade of ulcer, presence of neuropathy, and glycaemic level, were noted and correlated with the microbiota. The occurrence and establishment of bacterial biofilm over chronic wound tissues was revealed by Fluorescent in situ Hybridization and Scanning Electron Microscopy. The biofilm-forming ability of predominant bacterial isolates was studied via crystal violet assay and Confocal Laser Scanning Microscopy. The dominant phyla obtained from bacterial diversity analysis were Firmicutes, Proteobacteria, and Actinobacteria. The dominant aerobic pathogens identified by culture method are Pseudomonas, Proteus, Enterococcus, and Staphylococcus, whereas high-throughput sequencing revealed heightened levels of Streptococcus and Corynebacterium along with 22 different obligate anaerobes. The biofilm occurrence in chronic diabetic ulcer infection is well analysed. Herein, we illustrate the comprehensive pattern of bacterial infection and identify the community composition of chronic wound pathogenic biofilm.