Phytochemical profile and hepatoprotective potentiality of Phyllanthus genus: a review.

The Phyllanthus genus is very important plant traded as a raw herbal medicine in India. Commonly known as 'Bhumyamalaki' (Phyllanthus species) has been used for the prevention and treatment of jaundice. Phyllanthus is rich in diversity of bioactive compounds such as lignans, alkaloids, terpenoids, flavonoids, and tannins. Among some metabolites such as phyllanthin, hypophyllanthin, 8, 9-epoxy brevifolin, brevifolin, quercetin, gallic acid, elagic acid, and brevifolin carboxylate have been shown to have hepatoprotective and antioxidant activity found in this genus. The basic objective of this review was to overview the hepatoprotective activity based on the other available data from various plants of the Phyllanthus species including Phyllanthus amarus, Phyllanhtus urinaria, Phyllanthus fraternus, Phyllanthus maderaspatenis, Phyllanthus simplex, Phyllanthus emblica, Phyllanthus debillis, Phyllanthus tenellus, Phyllanthus polyphyllus, Phyllanthus reticulates, Phyllanthus indofischerii, Phyllanthus acidus, Phyllanthus niruri, Phyllanthus rheedii, Phyllanthus kozhikodianus, and Phyllanthus longiflorus. These species studied had considerable hepatoprotective potential. The secondary data, each in vitro and in vivo studies confirm the capacity of Phyllanthus species used as a remedy for jaundice or liver disease in addition to having antioxidants. Furthermore, it could be concluded that herbal drugs have the least side effects and are taken into considered safe for human health, they are able to substantially alternative synthetic drugs in the future.

Genomic insights into virulence, antimicrobial resistance, and adaptation acumen of Escherichia coli isolated from an urban environment.

Populations of common commensal bacteria such as Escherichia coli undergo genetic changes by the acquisition of certain virulence and antimicrobial resistance (AMR) encoding genetic elements leading to the emergence of pathogenic strains capable of surviving in the previously uninhabited or protected niches. These bacteria are also reported to be prevalent in the environment where they survive by adopting various recombination strategies to counter microflora of the soil and water, under constant selection pressure(s). In this study, we performed molecular characterization, phenotypic AMR analysis, and whole genome sequencing (WGS) of E. coli (n = 37) isolated from soil and surface water representing the urban and peri-urban areas. The primary aim of this study was to understand the genetic architecture and pathogenic acumen exhibited by environmental E. coli. WGS-based analysis entailing resistome and virulome profiling indicated the presence of various virulence (adherence, iron uptake, and toxins) and AMR encoding genes, including blaNDM-5 in the environmental isolates. A majority of our isolates belonged to phylogroup B1 (73%). A few isolates in our collection were of sequence type(s) (ST) 58 and 224 that could have emerged recently as clonal lineages and might pose risk of infection/transmission. Mobile genetic elements (MGEs) such as plasmids (predominantly) of the IncF family, prophages, pipolins, and insertion elements such as IS1 and IS5 were also observed to exist, which may presumably aid in the propagation of genes encoding resistance against antimicrobial drugs. The observed high prevalence of MGEs associated with multidrug resistance in pathogenic E. coli isolates belonging to the phylogroup B1 underscores the need for extended surveillance to keep track of and prevent the transmission of the bacterium to certain vulnerable human and animal populations. IMPORTANCE: Evolutionary patterns of E. coli bacteria convey that they evolve into highly pathogenic forms by acquiring fitness advantages, such as AMR, and various virulence factors through the horizontal gene transfer (HGT)-mediated acquisition of MGEs. However, limited research on the genetic profiles of environmental E. coli, particularly from India, hinders our understanding of their transition to pathogenic forms and impedes the adoption of a comprehensive approach to address the connection between environmentally dwelling E. coli populations and human and veterinary public health. This study focuses on high-resolution genomic analysis of the environmental E. coli isolates aiming to understand the genetic similarities and differences among isolates from different environmental niches and uncover the survival strategies employed by these bacteria to thrive in their surroundings. Our approach involved molecular characterization of environmental samples using PCR-based DNA fingerprinting and subsequent WGS analysis. This multidisciplinary approach is likely to provide valuable insights into the understanding of any potential spill-over to human and animal populations and locales. Investigating these environmental isolates has significant potential for developing epidemiological strategies against transmission and understanding niche-specific evolutionary patterns.

Comparative genome analysis of Pasteurella multocida strains of porcine origin.

Pasteurella multocida causes acute/chronic pasteurellosis in porcine, resulting in considerable economic losses globally. The draft genomes of two Indian strains NIVEDIPm17 (serogroup D) and NIVEDIPm36 (serogroup A) were sequenced. A total of 2182-2284 coding sequences (CDSs) were predicted along with 5-6 rRNA and 45-46 tRNA genes in the genomes. Multilocus sequence analysis and LPS genotyping showed the presence of ST50: genotype 07 and ST74: genotype 06 in NIVEDIPm17 and NIVEDIPm36, respectively. Pangenome analysis of 61 strains showed the presence of 1653 core genes, 167 soft core genes, 750 shell genes, and 1820 cloud genes. Analysis of virulence-associated genes in 61 genomes indicated the presence of nanB, exbB, exbD, ptfA, ompA, ompH, fur, plpB, fimA, sodA, sodC, tonB, and omp87 in all strains. The 61 genomes contained genes encoding tetracycline (54%), streptomycin (48%), sulphonamide (28%), tigecycline (25%), chloramphenicol (21%), amikacin (7%), cephalosporin (5%), and trimethoprim (5%) resistance. Multilocus sequence type revealed that ST50 was the most common (34%), followed by ST74 (26%), ST13 (24%), ST287 (5%), ST09 (5%), ST122 (3%), and ST07 (2%). Single-nucleotide polymorphism and core genome-based phylogenetic analysis clustered the strains into three major clusters. In conclusion, we described the various virulence factors, mobile genetic elements, and antimicrobial resistance genes in the pangenome of P. multocida of porcine origin, besides the rare presence of LPS genotype 7 in serogroup D.

Unraveling the evolutionary dynamics of toxin-antitoxin systems in diverse genetic lineages of Escherichia coli including the high-risk clonal complexes.

IMPORTANCE: Large-scale genomic studies of E. coli provide an invaluable opportunity to understand how genomic fine-tuning contributes to the transition of bacterial lifestyle from being commensals to mutualists or pathogens. Within this context, through machine learning-based studies, it appears that TA systems play an important role in the classification of high-risk clonal lineages and could be attributed to their epidemiological success. Due to these profound indications and assumptions, we attempted to provide unique insights into the ordered world of TA systems at the population level by investigating the diversity and evolutionary patterns of TA genes across 19 different STs of E. coli. Further in-depth analysis of ST-specific TA structures and associated genetic coordinates holds the potential to elucidate the functional implications of TA systems in bacterial cell survival and persistence, by and large.

Functional molecular characterization and the assessment of the transmission route of multidrug-resistant Helicobacter pullorum isolates from free-range and broiler chickens.

BACKGROUND: Some of the life-threatening, food-borne, and zoonotic infections are transmitted through poultry birds. Inappropriate and irrational use of antimicrobials in the livestock industry has resulted in an increased incidence of multi-drug resistant bacteria of epidemic potentials. MATERIALS AND METHODS: The adhesion and invasion properties of 11 free-range and broiler chicken derived Helicobacterpullorum isolates were evaluated. To examine the biofilm formation of H. pullorum isolates, crystal violet assay was performed. A quantitative assay of invasion-associated genes was carried out after infecting HepG2 cells with two different representative (broiler and free-range chicken) H. pullorum isolates, using RT-PCR assay. Furthermore, we investigated the prevalence of H. pullorum, Campylobacter jejuni and Salmonella spp. in chicken caeca and oviducts to determine the possibility of trans-ovarian transmission. RESULTS: All H. pullorum isolates adhered to HepG2 cells significantly but a notable difference towards their invasion potential was observed between free-range and broiler chicken isolates wherein broiler isolates were found to be more invasive compared to free-range isolates. Furthermore, cdtB, flhA and flaB genes of H. pullorum were upregulated post infection of HepG2 cells, in broiler chicken isolates compared to free-range chicken isolates. Moreover, all isolates of H. pullorum were found to form biofilm on the liquid-air interface of the glass coverslips and sidewalls of the wells with similar propensities. Despite presence of H. pullorum and C. jejuni in high concentrations in the caecum, they were completely absent in oviduct samples, thus ruling out the possibility of vertical transmission of these bacterial species. In contrast, Salmonella spp. was found to be present in a significant proportion in the oviduct samples of egg-laying hens suggesting its vertical transmission. CONCLUSIONS: Our findings suggest that H. pullorum, an emerging multi-drug resistant (MDR) pathogen could be transmitted from poultry sources to humans. In addition to this, its strong functional similarity with C. jejuni provides a firm basis for H. pullorum to be an emerging food-associated, MDR pathogenic bacterium that could pose risk to public health.

The third international hackathon for applying insights into large-scale genomic composition to use cases in a wide range of organisms.

In October 2021, 59 scientists from 14 countries and 13 U.S. states collaborated virtually in the Third Annual Baylor College of Medicine & DNANexus Structural Variation hackathon. The goal of the hackathon was to advance research on structural variants (SVs) by prototyping and iterating on open-source software. This led to nine hackathon projects focused on diverse genomics research interests, including various SV discovery and genotyping methods, SV sequence reconstruction, and clinically relevant structural variation, including SARS-CoV-2 variants. Repositories for the projects that participated in the hackathon are available at https://github.com/collaborativebioinformatics.

Genomic insights of beta-lactamase producing Klebsiella quasipneumoniae subsp. similipneumoniae belonging to sequence type 1699 from retail market fish, India.

Klebsiella quasipneumoniae is a recently described species and often misidentified as Klebsiella pneumoniae. Here, we report the genomic characterization of Klebsiella quasipneumoniae subsp. similipneumoniae (India238 strain) isolated from fish. The annotated genome acknowledged the presence of blaCTX-M-15, blaOKP-B-1, fosA5, oqxAB and virulence genes. The strain with ST1699 and serotypes KL52 and OL103 also harboured insertion sequences (ISs): ISKpn26 and ISEc9. Three complete phage genomes were identified in contigs 1 and 6 of the bacterial genome, enhancing the prospects of genome manipulation. The study highlights the pitfall of conventional microbiological identification methods to distinguish K. pneumoniae and K. quasipneumoniae. This is the first Indian study documenting the incidence of extended-spectrum beta-lactamase (ESBL)-producing K. quasipneumoniae subsp. similipneumoniae from a non-clinical environment, equipped with virulomes and associated mobile genetic elements. Given that fish can act as a potential vector for transmission of antimicrobial resistance genes, our findings have paramount importance on human health.

Whole-genome sequence analysis of Clostridium chauvoei isolated from clinical case of black quarter (BQ) from India.

Black quarter (BQ) is an infectious disease affecting cattle and small ruminants worldwide caused by Gram-positive anaerobic bacterium Clostridium chauvoei. In this study, a draft genome sequence of C. chauvoei NIVEDIBQ1 strain isolated from clinical case of black quarter was analyzed. Sequence analysis indicated that genome had 2653 predicted coding DNA sequences, harbored numerous genes, mobile genetic elements for pathogenesis, and virulence factors. Computational analysis revealed that strain contained 30 virulence-associated genes. An intact genomic region highly similar to the Clostridium phage was present in the genome. Presence of CRISPR systems and the transposon components likely contribute to the genome plasticity. Strain encode diverse spectrum of degradative carbohydrate-active enzymes (CAZymes). Comparative SNP analysis revealed that the genomes of the C. chauvoei strains analyzed were highly conserved. Phylogenetic analysis of strains and available genome (n = 21) based on whole-genome multi-locus sequence typing (wgMLST) and core orthologous genes showed the clustering of strains into two different clusters suggesting geographical links.

Comparative genome analysis of Pasteurella multocida serogroup B:2 strains causing haemorrhagic septicaemia (HS) in bovines.

Pasteurella multocida, a Gram-negative bacterium with ubiquitous nature, is known to affect wide range of host species worldwide with varied clinical manifestations including haemorrhagic septicaemia (HS) in bovines. Although, HS causing P. multocida strains were identified and characterized by conventional tools and PCR assays, diverse strains are indistinguishable by these tools in the face of disease outbreaks. In this study, draft genomes of three virulent P. multocida serotype B:2 strains (NIVEDIPm32, NIVEDIPm34 and NIVEDIPm35) were analyzed following whole genome sequencing, assembly, annotation and compared them with existing global genomes (n = 43) of bovine origin in the database. Three draft genomes of NIVEDIPm strains consisted of 40-52 contigs with GC content of ∼40.4%. The genome size and predicted genes content was ∼2.3 Mb and 2181-2189, respectively. Besides, the presence of various mobile genetic elements, antimicrobial resistance genes and biofilm related genes suggested their vital roles in virulence; further, adaptation to the host immune system as well as host pathogen interaction. Multi locus sequence analysis based on RIRDC scheme showed the presence of ST122 in all the three strains. wgMLST based phylogenic analysis suggested that HS causing Indian virulent field strains differed geographically and showed diversity from existing HS vaccine strain P52. The phylogenetic tree revealed that North Indian strains share high similarity with strains of Pakistan than South Indian Strain. Notably, a high divergence of SNPs between the HS causing circulating virulent strains of India and current HS vaccine strain P52 suggested an imminent need for relook in to HS vaccination strategy for livestock in India.

Whole-genome sequence analysis of Staphylococcus aureus from retail fish acknowledged the incidence of highly virulent ST672-MRSA-IVa/t1309, an emerging Indian clone, in Assam, India.

The epidemiology and toxigenicity of MRSA in the fishery environment are poorly understood. In this study, methicillin-resistant Staphylococcus aureus (MRSA) (n = 1) and methicillin-susceptible S. aureus (MSSA) (n = 2) from retail fish were subjected to comprehensive genome analysis. Here, we report the occurrence of ST672-MRSA-IV/t1309 and ST5-MSSA/t105 for the first time from India in the fishery environment. The resistome of the isolates was in concordance with their phenotypic resistance pattern. Phenotypically, the resistance profile of MSSA isolates (n = 2) was AMP-CLI-ERY-NOR-PEN. For MRSA (n = 1), it was AMP-CFZ-CLI-ERY-NOR-OXA-PEN. The antibiotic efflux genes and mutations in the antibiotic target accounted for fluoroquinolone resistance whereas methicillin resistance was conferred through possession of a mecA gene. Similarly, all three isolates carried a similar array of virulence factors. The conjugative plasmid inc18 and rep family 10 plasmids were found in two of the three isolates. This study documents the MRSA carrying SCCmec IVa elements which are the markers of community-associated MRSA (CA-MRSA). Through the possession of SCCmec IV elements, which are smaller than other types of SCCmec, MRSA can contribute to the rapid dissemination of antimicrobial resistance and virulence factors. In short, our findings highlighted that the presence of ST672-MRSA in fishery environments may pose a risk to human health.

Antibiotic resistance patterns of Staphylococcus aureus: A multi center study from India.

Chemotherapy and emergence of drug resistance strains of Staphylococcus aureus is receiving serious threats, due to the origin and spread of hospital and community acquired MDR strains. The present study reports the prevalence of antibiotic resistance among Staphylococcus aureus isolated from clinical samples from different cities of India. Antibiotic sensitivity was performed by Kirby-Bauer disk diffusion method and minimum inhibitory concentrations were determined for vancomycin and methicillin according to CLSI (2014) guidelines. A total of 212 S. aureus were obtained from different samples such as pus, blood, urine. The antibiogram of these isolates indicated widespread resistance to various groups of antibiotics ranging from a minimum of 10.13% against Phenicols (Chloramphenicol) to a maximum of 97% against Penicillin and 44.8% isolates were MRSA and alarmingly 10.84% were VRSA. Most of the MRSA isolates showed inducible Clindamycin resistance. Widespread prevalence of MDR patterns, increasing incidence of MRSA and VRSA calls for exploration of alternative medicines and new approaches to combat Staphylococcal infections.