Phylogenomics of the Phylum Proteobacteria: Resolving the Complex Relationships.

Proteobacteria is one of the largest and phenotypically most diverse divisions within the domain bacteria. Due to the economic importance, this phylum demands an urgent need for a clear and scientifically sound classification system to streamline their characterization. The goal of our study was to carefully reevaluate the current system of classification and suggest changes wherein necessary. Phylogenetic trees of 84 Proteobacteria were constructed using single gene-based phylogeny involving 16S rRNA genes and protein sequences of 85 conserved genes, whole genome-based phylogenetic tree using CVtree3.0, amino acid Identity matrix tree, and concatenated tree with aforementioned conserved genes. The results of our study confirm the polyphyletic relationship between Desulfurella acetivorans, a Deltaproteobacteria with Epsilonproteobacteria. The group Syntrophobacterales was found to be polyphyletic with respect to Desulfarculus baarsii and the group Thiotrichales was found to be splitting in different phylogenetic trees. Placement of phylogenetic groups belonging to Rhodocyclales, Oceonospirilalles, and Chromatiales is controversial and requires further study and revisions. Based on our analysis, we strongly support reclassification of Magnetococcales as a separate class Etaproteobacteria. From our results, we conclude that concatenated trees of conserved proteins are a more accurate method for phylogenetic analysis, as compared to other methods used.

A Phytochemicals Approach Towards the Treatment of Cervical Cancer Using Polyphenols and Flavonoids.

AIM: Despite enormous progress in cancer biology, oncologists are still struggling to retrieve the methods and drugs to cure cancer which remains a global threat to humans. Plant-derived natural compounds, also known as phytochemicals, carry therapeutic potential and could be taken as dietary supplements, which are a radical way to resist as well as cure cancer. The present study reveals the anti-cancerous potential of a few phytochemical constituents under in vitro conditions and their mode of action on cervical cancer. SiHa was treated with phytochemicals viz. Quercetin dihydrate, Gallic Acid, and Naringin with varying concentrations to assess their cytotoxicity potential by various methods and also to elucidate their IC50 values. METHODS: All three compounds reduced the cell number and viability, along with alterations in cancer cell morphology. The diagnosed IC50 values of the compounds were 160µM, 200µM, and 1500µM for Quercetin dihydrate, Gallic Acid, and Naringin, respectively. DNA fragmentation assay and gene expression analysis were also used to assess apoptosis and anti-proliferative activity of compounds. RESULTS: We found fragmented DNA in treated cells as assessed by gel electrophoresis assay. These phytochemicals elicit an apoptotic response in SiHa cells by significantly up-regulating the gene expression level of p53 and p21 (p-value <0.005). CONCLUSION: Considering the anti-cancer and anti-proliferative potential of Quercetin dihydrate, Gallic Acid, and Naringin on the cervical cancer cell line, these phytochemicals could be used as an alternative or concurrent cancer therapeutic approach. However, further in-depth elucidation of their mode of action, safety, and efficacy should be explored.

Bioactive compounds and their libraries: An insight into prospective phytotherapeutics approach for oral mucocutaneous cancers.

Oral mucocutaneous cancers (OMCs) are cancers that affect both the oral mucosa and perioral cutaneous structures. Common OMCs are squamous cell carcinoma (SCC), basal cell carcinoma (BCC) and malignant melanoma (MM). Anatomical similarities and conventions which categorizes these lesions blur the magnitude of OMCs in diverse populations. The burden of OMC is high in the sub-Saharan Africa and Indian subcontinents, and the cost of management is prohibitive in the resource-limited, developing world. Hence, there is a pressing demand for the use of cost-effective in silico approaches to identify diagnostic tools and treatment targets for diseases with high burdens in these regions. Due to their ubiquitousness and accessibility, the use of therapeutic efficacy of plant bioactive compounds in the management of OMC is both appropriate and plausible. Furthermore, screening known mechanistic disease targets with well annotated plant bioactive compound libraries is poised to improve the routine management of OMCs provided that the requisite access to database resources are available and accessible. Using natural products minimizes the side effects and morbidities associated with conventional therapies. The development of innovative treatments approaches would tremendously benefit the African and Indian populace and reduce the mortalities associated with OMCs in the developing world. Hence, we discuss herein, the potential benefits, opportunities and challenges of using bioactive compound libraries in the management of OMCs.

Essential amino acid profiling of the four lac hosts belonging to genus Flemingia: its implications on lac productivity.

The Indian lac insect (Kerria lacca), a hemipteran, phloem sap sucking sedentary insect is an important bioresource which thrives on tender twigs of more than 400 plant species belonging to various genera and families. The most common commercial host plants for lac cultivation are big trees hence cultivation was concentrated mainly to dense forests across the country till last decade. Recently, a new bushy host plant belonging to the genus Flemingia has been introduced so that lac can be cultivated on farmlands like other cash crops. The insect is sedentary and feeds on the phloem sap of the host plants, the only source of its nutrition. Interestingly, the biological attributes of the insect as well as the qualitative and quantitative production of lac is influenced by the host plant on which the insect feeds upon. The present study was thus aimed at deciphering the effect of phloem sap constituents obtained from four plant host taxa belonging to the same genus Flemingia viz. F. semialata, F. macrophylla, F. bracteata and F. chapar (essential amino acids only-EAAs) on lac productivity. Moreover, a newer method for phloem sap collection i.e. Dot-blot in addition to the facilitated exudation using EDTA was also investigated. Dot-blot method for phloem sap collection also came out to be a promising method for field studies; although slightly higher concentration of EAAs were obtained from EDTA method, thus the later was used for further analysis. Phloem sap of four plant host taxa belonging to the same genus Flemingia were qualitatively and quantitatively analysed for seven EAAs (Arginine, Glycine, Leucine, Methionine, Phenylalanine Tyrosine and Valine). Amino acid concentration regime and further analysis done using statistical tools (ANOVA and PCA) points out the EAA concentration in the phloem sap is in congruency with the lac production data obtained through previous studies as F. semialata > F. macrophylla > F. chapar > F. bracteata. The present study thus scientifically points out that F. semialata can be a promising plant for lac cultivation on the basis of higher EAA content as compared to the rest three.

Genetic diversity and genetic relationships in Hyacinthaceae in India using RAPD and SRAP markers.

Genetic diversity and relationship among three genera namely Drimia, Dipcadi and Ledebouria of Hyacinthaceae in India was studied using RAPD and SRAP markers. Twenty one RAPD primers and nine SRAP were used for analyzing 41 accessions. RAPD gave an average 12.6 markers per primer, while SRAP generated 10.1 markers per primer pair. The family emerged very diverged with high polymorphism. The study resolved the three genera into monophyletic groups corresponding to three subfamilies; Urginoideae, Hyacinthoideae and Ornithogaloideae. Drimia wightii emerged a very distinct species and species specific markers were obtained with both marker systems. AMOVA analysis also revealed the genera to be quite well diverged. The two markers showed high correlation (r = 0.932) in Mantel matrix crresspondance test. The combined data also showed a very good correlation with the respective markers individually.

Genetic diversity and population structure of Butea monosperma (Lam.) Taub.- a potential medicinal legume tree.

Three molecular marker systems, Random Amplified Polymorphic DNA (RAPD), Inter-Simple Sequence Repeats (ISSR) and Sequence-Related Amplified Polymorphism (SRAP) were employed to investigate the genetic structure and diversity among the 14 natural populations of Butea monosperma collected from different geographical regions of India. Detected by 17 RAPD, 15 ISSR and 11 SRAP primer combinations, the proportions of polymorphic bands were 84.2 %, 77.2 % and 91.9 %, respectively, and the mean Nei's genetic distances among the populations were 0.13, 0.10 and 0.13, respectively. Partitioning of genetic variability by Analysis of molecular variance (AMOVA) revealed that the high genetic diversity was distributed within the populations. AMOVA also revealed that the coefficient of gene differentiation among populations based on FST was very high irrespective of markers used. The overall gene flow among populations (Nm) was very low. Cophenetic correlation coefficients of Nei's distance values and clustering pattern by Mental test were statistically significant for all three marker systems used but poor fit for ISSR data than for RAPD, SRAP and combined data set of all three markers. For all markers, a high similarity in dendrogram topologies was obtained, although some differences were observed with ISSR. The dendrogram obtained by RAPD, SRAP and combined data set of all three markers reflect relationship of most of the populations according to their geographic distribution.

"Phloem sap analysis of Schleichera oleosa (Lour) Oken, Butea monosperma (Lam) Taub. and Ziziphus mauritiana (Lam) and hemolymph of Kerria lacca (Kerr) using HPLC and tandem mass spectrometry".

Females of lac insects especially of Kerria lacca (Kerr) secret a resin known as lac for their own protection, which has tremendous applications. Lac insect completes its lifecycle on several host taxa where it exclusively feeds on phloem sap but Schleichera oleosa (Lour.) Oken, Butea monosperma (Lam.) and Ziziphus mauritiana (Lam.) are its major hosts. Analysis of phloem sap constituents as well as hemolymph of lac insect is important because it ultimately gets converted into lac by insect intervention. Main phloem sap constituent's viz. sugars and free amino acids and hemolymph of lac insect were analyzed using HPLC and tandem mass spectrometry, respectively. The results were transformed to relative percentage of the total sugars and free amino acids analyzed in each sample for comparison among lac insect hemolymph and the phloem sap of the three different host taxa. Sucrose (58.9 ± 3.6-85.6 ± 0.9) and trehalose (62.3 ± 0.4) were the predominant sugars in phloem sap of three taxa and hemolymph of lac insect, respectively. Glutamic acid (33.1 ± 1.4-39.8 ± 1.4) was found to be main amino acid among the phloem sap of three taxa while tyrosine (61 ± 2.6) was the major amino acid in hemolymph of lac insect. The relative percentage of non-essential amino acids (60.8 %-69.9 %) was found to be more in all the three host taxa while essential amino acids (30.1 %-35.4 %) were present at a lower relative percentage. In contrast to this, the relative percentage of essential amino acids (81.9 %) was observed to be higher as compared to non-essential amino acids (17.7 %) in lac insect hemolymph. These results led to the detection of lac insect's endosymbionts. Moreover, this study revealed a clue regarding the importance of development of a synthetic diet for this insect so that a precise pathway of lac biosynthesis could be investigated for thorough understanding.

Co-existence, phylogeny and putative role of Wolbachia and yeast-like symbiont (YLS) in Kerria lacca (Kerr).

This study reports the first detection of Wolbachia and yeast-like symbiont (YLS) harbored in Kerria lacca (Kerr), a scale insect, latter of which produces an economically important natural resin, known as lac. Wolbachia was detected using PCR amplification and sequencing of 16S rDNA; and further confirmation and phylogenetic analysis was carried out by fast evolving wsp gene. Neighbor-joining and maximum parsimonious (MP) analysis showed that this strain belongs to subgroup "ori" of Wolbachia super group B of arthropods. Wolbachia of K. lacca is hereby designated as "wKerlac" according to Wolbachia nomenclature system. Histological study revealed the presence of yeast-like endosymbiont, which was also confirmed by PCR amplification of 18S rDNA. Phylogenetic analysis revealed that YLS of K. lacca is quite distinct from YLS of aphid, planthoppers, and beetles. Putative roles of Wolbachia in lecanoid chromosome system of sex determination and in biased sex ratio of K. lacca populations; and YLS in nutritional supplementation and detoxifying substances which are deleterious to K. lacca, are hereby, suggested.