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DNA barcoding is a powerful method for the identification of lichenized fungi groups for which the diversity is already well-represented in nucleotide databases, and an accurate, robust taxonomy has been established. However, the effectiveness of DNA barcoding for identification is expected to be limited for understudied taxa or regions. One such region is Antarctica, where, despite the importance of lichens and lichenized fungi identification, their genetic diversity is far from characterized. The aim of this exploratory study was to survey the lichenized fungi diversity of King George Island using a fungal barcode marker as an initial identification tool. Samples were collected unrestricted to specific taxa in coastal areas near Admiralty Bay. Most samples were identified using the barcode marker and verified up to the species or genus level with a high degree of similarity. A posterior morphological evaluation focused on samples with novel barcodes allowed for the identification of unknown Austrolecia, Buellia, and Lecidea s.l. species. These results contribute to better represent the lichenized fungi diversity in understudied regions such as Antarctica by increasing the richness of the nucleotide databases. Furthermore, the approach used in this study is valuable for exploratory surveys in understudied regions to guide taxonomic efforts towards species recognition and discovery.

Objective: To undertake the first detailed genomic analysis of methicillin-resistant Staphylococcus aureus (MRSA) isolated in Sri Lanka.\ud Methods: A prospective observational study was performed on 94 MRSA isolates collected over a four month period from the Anuradhapura Teaching Hospital, Sri Lanka. Screening for mecA, mecC and the Panton-Valentine leucocidin (PVL) -associated lukS-PV/lukF-PV genes and molecular characterisation by spa typing was undertaken. Whole genome sequencing (WGS) and phylogenetic analysis was performed on selected multilocus sequence type (MLST) clonal complex 5 (CC5) isolates from Sri Lanka, England, Australia and Argentina.\ud Results: All 94 MRSA harboured the mecA gene. Nineteen spa types belonging to nine MLST clonal complexes were identified. Where origin of the sample was recorded, most isolates were from skin and soft tissue infections (70/91; 76.9%), with fewer causing bacteraemia (16/91; 17.6%), empyema (3/91; 3.3%) and osteomyelitis (2/91; 2.2%). Sixty two (65.9%) isolates were PVL positive with the majority (56 isolates; 90.3%) belonging to a dominant CC5 lineage. This lineage, PVL-positive ST5-MRSA-IVc, was associated with both community and hospital-onset infections. Based on WGS, representative PVL-positive ST5-MRSA-IVc isolates from Sri Lanka, England and Australia formed a single phylogenetic clade, suggesting wide geographical circulation.\ud Conclusions: We present the most detailed genomic analysis of MRSA isolated in Sri Lanka to date. The analysis identified a PVL-positive ST5-MRSA-IVc that is prevalent among MRSA causing clinical infections in Sri Lanka. Furthermore, this clone was also found among isolates from the United Kingdom and Australia.

Peperomia R. & P. pertenece a la familia Peperomia cuyos miembros se encuentran en los trópicos de ambos hemisferios, con mayor concentración y centros de dispersión en Latino América y Malasia. Peperomia es el segundo más grande genero dentro de las Piperaceae con alrededor de 1000 especies ampliamente distribuidas en regiones tropicales y subtropicales. Especies de Peperomia son consideradas generalmente como plantas ornamentales; sin embargo, muchas de ellas son utilizadas como plantas medicinales en la Sierra peruana, en casi toda la Costa y Selva del Perú, así como también en otras partes del mundo ya que producen una gran cantidad de metabolitos secundarios. Se ha reportado actividad antipirética, antiinflamatoria, cicatrizante y analgésica para algunas especies, así como también efecto antibacterial, anticonvulsivo y antitumoral. A pesar de que las plantas de este género son fácilmente distinguibles en campo mediante la combinación de sus características vegetativas y morfológicas, la uniformidad de sus diminutas flores y la gran cantidad de especies en el género han dificultado el desarrollo de una clasificación intragenérica estable. La diversidad genética entre las especies de Peperomia fue evaluada utilizando las regiones plástidicas matK y rbcL y la Región Espaciadora Transcriptora Interna 2 (Intergenic Spacer region – ITS2) del ADN ribosomal nuclear. Las secuencias fueron evaluadas en 167 plantas de Peperomia de 41 especies. Utilizando la información de rbcL y matK combinada se construyeron dendogramas en los que se logró agrupar 64 individuos en 7 grupos de especies. Sin embargo, la variación presente en la región ITS2 nos permitió obtener nodos de mayor soporte estadístico con valores de bootstrap entre 91-100% y un rango de divergencia de 0-0.003 dentro de una misma especie y 0.041-0.308 entre especies diferentes.