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Leucomeris decora is a traditional medicinal plant that is listed as an endangered species in China. Recently, L. decora has become locally rare. Here the complete chloroplast genome of L. decora was assembled and reported for the first time. Its plastome was 151,491 bp in length, including a large single-copy region (LSC; 83,155 bp), a small single-copy region (SSC; 18,216 bp), and a pair of inverted repeated regions (IRa and IRb; 25,060 bp). The overall GC content was 37.8%, and the genome contains 134 genes, including 92 protein-coding genes, 8 rRNA genes, and 34 tRNA genes. Phylogenetic analysis of thirteen representative species from the family of Asteraceae showed that L. decora is clustered into one clade with Gerbera jamesonii with high bootstrap values, indicating a close relationship between these two species.

This study investigated the prevalence, distribution, and genotypes of adenoviruses (AdVs) and noroviruses (NoVs) in the Puzi River and surrounding areas in Taiwan. The viruses in the water samples were isolated using the membrane filtration method and the viral nucleic acids were extracted. The RNA of NoVs was reverse‐transcribed into complementary DNA using reverse transcriptase‐polymerase chain reaction. AdVs and NoVs were detected using nested PCR. Genotyping and phylogenetic analyses were performed to identify the various viral genotypes in the water samples. Human adenovirus (HAdVs) and porcine adenovirus (PAdVs) were the predominant genotypes in the water samples. The prevalence of F species HAdVs serotype 41 (79.2%) and C species PAdVs serotype 5 (18.1%) was higher than that of other serotypes. Among NoVs, genogroup GII was more prevalent than GI. In particular, GII.4 (21.2%) and GII.17 (18.2%) were the predominant genotypes, which was consistent with the clinical findings. The prevalence of both AdVs and NoVs was higher in the winter than spring, summer and autumn seasons. AdVs and NoVs detection results were statistically analyzed by investigating their association with water quality indicators. The results revealed that the presence of AdVs was significantly correlated with the heterotrophic bacterial count, total coliform Escherichia coli, turbidity, salinity, and dissolved oxygen. Meanwhile, the presence of NoVs was only significantly correlated with temperature, pH, and dissolved oxygen. Microbial pollution sources may include urban runoff and discharge of water from livestock farms situated near the river and tributaries within this region of Taiwan. Future studies should include comparisons of the presence of AdVs and NoVs in these known pollution sources and water quality monitoring of these watersheds, as this will allow potential identification of pollution sources. Additionally, remediation strategies must be developed to minimize viral contamination in the river ecosystem., Key Points AdVs prevalence is higher in the river than in other sitesHAdV 41 and PAdV 5 are the dominant genotypes over all sample sitesDominant NoVs genotypes are GII.4 and GII.17, they were associated with clinical cases

Salmonella enterica subspecies enterica serovar Enteritidis is one of the major foodborne zoonotic pathogens globally. It has significantly impacted human health and global trade. In this investigation, whole-genome sequencing was employed to determine the antimicrobial resistance (AMR) pattern of a collection of Salmonella Enteritidis isolated from humans, poultry, and food sources. The study also investigated the virulence genes profile of the isolates as well as the phylogenetic relationships among strains. Illumina NextSeq technology was used to sequence the genome of 82 Salmonella Enteritidis strains isolated over 3 years (2016–2018) in Peninsular Malaysia. The pattern of resistance showed that tetracycline had the highest frequency (37/82, 45.12%), and isolates from food samples showed the highest rate of 9/18 (50.00%), followed by human 17/35 (48.57%) and then poultry 11/29 (37.93%). The second drug with the highest resistance rate is ampicillin with 5/29 (17.24%) for poultry, 4/35 (11.43%) for human, and 0/18 (0.00%) for food isolates respectively. Similarly, a total of 19 antimicrobial resistance (AMR) genes corresponding to the nine drugs used in the disc diffusion assay were evaluated from the whole genome sequence data. The aminoglycoside resistance gene aac(6′)-ly was detected in 79 of the 82 isolates (96.34%). While the phylogenetic analysis revealed distinct lineages isolated, the three sources indicating possible cross-contamination. In conclusion, the results showed that the genomic profile of Salmonella Enteritidis isolated from humans, poultry, and food samples share genetic traits, hence the need to institute measures at controlling the continuous spread of these resistant pathogens.

Salmonella enterica subspecies enterica serovar Enteritidis is one of the major foodborne zoonotic pathogens globally. It has significantly impacted human health and global trade. In this investigation, whole-genome sequencing was employed to determine the antimicrobial resistance (AMR) pattern of a collection of Salmonella Enteritidis isolated from humans, poultry, and food sources. The study also investigated the virulence genes profile of the isolates as well as the phylogenetic relationships among strains. Illumina NextSeq technology was used to sequence the genome of 82 Salmonella Enteritidis strains isolated over 3 years (2016–2018) in Peninsular Malaysia. The pattern of resistance showed that tetracycline had the highest frequency (37/82, 45.12%), and isolates from food samples showed the highest rate of 9/18 (50.00%), followed by human 17/35 (48.57%) and then poultry 11/29 (37.93%). The second drug with the highest resistance rate is ampicillin with 5/29 (17.24%) for poultry, 4/35 (11.43%) for human, and 0/18 (0.00%) for food isolates respectively. Similarly, a total of 19 antimicrobial resistance (AMR) genes corresponding to the nine drugs used in the disc diffusion assay were evaluated from the whole genome sequence data. The aminoglycoside resistance gene aac(6′)-ly was detected in 79 of the 82 isolates (96.34%). While the phylogenetic analysis revealed distinct lineages isolated, the three sources indicating possible cross-contamination. In conclusion, the results showed that the genomic profile of Salmonella Enteritidis isolated from humans, poultry, and food samples share genetic traits, hence the need to institute measures at controlling the continuous spread of these resistant pathogens.

A study of Newcastle disease virus (NDVs) using molecular characterization in indigenous chickens in Plateau State was carried out. The birds were obtained from three geographical locations in Plateau State. Three ribonucleic acids (RNAs) of Newcastle disease viruses (NDVs) obtained from normal indigenous chickens, which were never vaccinated against Newcastle disease (ND) were characterized. These RNAs were named Lc 3, Lc 4 and Lc5, respectively. These three samples were genotypically analyzed using reverse transcription polymerase chain reaction (RT-PCR) with primers specific to the viral fusion (F) protein gene. The deduced amino acid sequences at the F0 of these three RNA between positions 112 and 117 were all the same. The three NDV RNA had phenylalanine (F) residue at position 117, confirming their high virulence to indigenous chicken in Plateau State, Nigeria. The existence of virulent NDVs in circulation in indigenous chicken could be a serious threat to commercial chicken. The fragment of the deduced amino acid sequences were compared phylogenetically and were all found to belong to the genotype 5 g. To the best of our knowledge, this is the first reported genotype Vg strains that possess the sequences of 112R-R-Q-K-R-F117 within the F0 protein in indigenous chickens in Plateau State, Nigeria. They also grouped/clustered together with a Niger Republic strain (FJ772475 chicken-2602-605-Niger-2008, FJ772481chicken-2602-625-Niger-2008), and another strain from Cameroon (FJ772484chicken-3490-147-cameroon-2008). This study presents for the first time to the best of our knowledge report of not only the presence of the velogenic strain, but has gone ahead to establish the amino acid sequences, and the phylogenic ancestral history of these novel Nigerian NDV isolates, and their accession numbers as well as their relatedness to already established isolates. The information obtained in this study could be useful for improving the knowledge on the epidemiology, spread, efficiency of prevention/control strategies currently in place in Nigeria and indeed the West African sub-region.

Prokaryotic MazF family toxins cooccur with cognate antitoxins having divergent DNA-binding folds and can be of chromosomal or plasmid origin. Sequence similarity search was carried out to identify the Toxin–Antitoxin (TA) operons of MazF family followed by sequence analysis and phylogenetic studies. The genomic DNA upstream of the TA operons was searched for the presence of regulatory motifs. The MazF family toxins showed a conserved hydrophobic pocket in a multibinding site and are present in pathogenic bacteria. The toxins of the MazF family are associated with four main types of cognate antitoxin partners and cluster as a subfamily on the branches of the phylogenetic tree. This indicates that transmission of the entire operon is the dominant mode of inheritance. The plasmid borne TA modules were interspersed between the chromosomal TA modules of the same subfamily, compatible with a frequent interchange of TA genes between the chromosome and the plasmid akin to that observed for antibiotic resistance gens. The split network of the MazF family toxins showed the AbrB-linked toxins as a hub of horizontal gene transfer. Distinct motifs are present in the upstream region of each subfamily. The presence of MazF family TA modules in pathogenic bacteria and identification of a conserved binding pocket are significant for the development of novel antibacterials to disrupt the TA interaction. However, the role of TAs in stress resistance needs to be established. Phylogenetic studies provide insight into the evolution of MazF family TAs and effect on the bacterial genome.

Avian metapneumoviruses detected in Northern Italy between 1987 and 2007 were sequenced in their fusion (F) and attachment (G) genes together with the same genes from isolates collected throughout western European prior to 1994. Fusion protein genes sequences were highly conserved while G protein sequences showed much greater heterogeneity. Phylogenetic studies based on both genes clearly showed that later Italian viruses were significantly different to all earlier virus detections, including early detections from Italy. Furthermore a serine residue in the G proteins and lysine residue in the fusion protein were exclusive to Italian viruses, indicating that later viruses probably arose within the country and the notion that these later viruses evolved from earlier Italian progenitors cannot be discounted. Biocomputing analysis applied to F and G proteins of later Italian viruses predicted that only G contained altered T cell epitopes. It appears likely that Italian field viruses evolved in response to selection pressure from vaccine induced immunity.

Acanthoscelides Schilsky is a large genus of neotropical bruchid beetles, in which most species show host plant specialization. Acanthoscelidesobtectus and Acanthoscelides obvelatus are two sibling species specialized on Phaseolus beans, and are therefore considered pests. Up to now, thestatus of these two taxa has remained unclear, the few studies conducted having failed to elucidate whether these are two differentiated species ora single morphologically variable species. In addition, A. obvelatus has not been taken into account in the great majority of studies of beanbruchids. In this morphological and genetic study, we show that A. obtectus and A. obvelatus are two true non-hybridizing species, whichdiverged about 22 Mya. Although the two species demonstrate only few morphological differences, we point out some diagnostic characters thatenable their identification in the field. We also address a genetic method of differentiation of the two species, based on species-specificmicrosatellite loci. The strong morphological resemblance of these two species, despite their ancient divergence, may be the result of evolutionarystasis, which could be the consequence of stabilizing selection. Niche differentiation could enable the two species to coexist indefinitely.Key words: Sibling species – bruchids – coleoptera – phylogenetic studies – evolutionary stasis

Background Similarity of sequences is a key mathematical notion for Classification and Phylogenetic studies in Biology. It is currently primarily handled using alignments. However, the alignment methods seem inadequate for post-genomic studies since they do not scale well with data set size and they seem to be confined only to genomic and proteomic sequences. Therefore, alignment-free similarity measures are actively pursued. Among those, USM (Universal Similarity Metric) has gained prominence. It is based on the deep theory of Kolmogorov Complexity and universality is its most novel striking feature. Since it can only be approximated via data compression, USM is a methodology rather than a formula quantifying the similarity of two strings. Three approximations of USM are available, namely UCD (Universal Compression Dissimilarity), NCD (Normalized Compression Dissimilarity) and CD (Compression Dissimilarity). Their applicability and robustness is tested on various data sets yielding a first massive quantitative estimate that the USM methodology and its approximations are of value. Despite the rich theory developed around USM, its experimental assessment has limitations: only a few data compressors have been tested in conjunction with USM and mostly at a qualitative level, no comparison among UCD, NCD and CD is available and no comparison of USM with existing methods, both based on alignments and not, seems to be available. Results We experimentally test the USM methodology by using 25 compressors, all three of its known approximations and six data sets of relevance to Molecular Biology. This offers the first systematic and quantitative experimental assessment of this methodology, that naturally complements the many theoretical and the preliminary experimental results available. Moreover, we compare the USM methodology both with methods based on alignments and not. We may group our experiments into two sets. The first one, performed via ROC (Receiver Operating Curve) analysis, aims at assessing the intrinsic ability of the methodology to discriminate and classify biological sequences and structures. A second set of experiments aims at assessing how well two commonly available classification algorithms, UPGMA (Unweighted Pair Group Method with Arithmetic Mean) and NJ (Neighbor Joining), can use the methodology to perform their task, their performance being evaluated against gold standards and with the use of well known statistical indexes, i.e., the F-measure and the partition distance. Based on the experiments, several conclusions can be drawn and, from them, novel valuable guidelines for the use of USM on biological data. The main ones are reported next. Conclusion UCD and NCD are indistinguishable, i.e., they yield nearly the same values of the statistical indexes we have used, accross experiments and data sets, while CD is almost always worse than both. UPGMA seems to yield better classification results with respect to NJ, i.e., better values of the statistical indexes (10% difference or above), on a substantial fraction of experiments, compressors and USM approximation choices. The compression program PPMd, based on PPM (Prediction by Partial Matching), for generic data and Gencompress for DNA, are the best performers among the compression algorithms we have used, although the difference in performance, as measured by statistical indexes, between them and the other algorithms depends critically on the data set and may not be as large as expected. PPMd used with UCD or NCD and UPGMA, on sequence data is very close, although worse, in performance with the alignment methods (less than 2% difference on the F-measure). Yet, it scales well with data set size and it can work on data other than sequences. In summary, our quantitative analysis naturally complements the rich theory behind USM and supports the conclusion that the methodology is worth using because of its robustness, flexibility, scalability, and competitiveness with existing techniques. In particular, the methodology applies to all biological data in textual format. The software and data sets are available under the GNU GPL at the supplementary material web page.

Aphids are morphologically simple. Their numerous hypothesized convergent reductions, such as reduced siphunculi length in association with ant attendance, have made it difficult to define morphological synapomorphies that are necessary for phylogenetic studies. Thus, I used molecular characters both to reexamine the phylogenetic relationships of Cavariella and Pterocommatinae within Aphididae, and to further map host associations and life cycles onto these phylogenies to better understand the evolutionary lability of host alternation within Aphididae. Independent and combined analyses were performed under unweighted parsimony and maximum likelihood criteria for sequences of mitochondrial cytochrome oxidase II plus tRNA-Leucine plus partial cytochrome oxidase I (COII + trnL), and nuclear elongation factor-�� (EF1��). Shimodaira-Hasegawa likelihood ratio tests were also employed to test for statistically significant differences between: (1) the tree topologies obtained from the analyses in this study; and (2) topologies supporting the traditional phylogenetic hypotheses based upon morphological data. These analyses recovered various relationships contradicting the current morphology-based phylogeny: 1) a highly supported sister relationship of Pterocommatinae to Cavariella; 2) paraphyly of Myzinae and Anuraphidinae, as well as paraphyly in some genera within Dactynotinae; and 3) support for the sister relationship of Pterocommatinae/Cavariella/Liosomaphis to the remaining macrosiphines. There was also evidence within Aphididae for an evolutionary rapid radiation and multiple origins of host-alternation. These results imply the need for further molecular analyses in resolving relationships within Macrosiphini, and for defining the morphological attributes that characterize these relationships.