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Albaqami, A.

Publications and source records attributed to Albaqami, A..

2 recordsLinked to original sources

Comprehensive genomic analysis of Klebsiella pneumoniae and its temperate N-15-like phage: From isolation to functional annotation

A temperate N-15-like phage and an extensively drug-resistant (XDR) Klebsiella pneumoniae strain were studied in this research. The former was found in hospital wastewater, while the latter was retrieved from the sputum of an intensive care unit patient. The bacteria showed strong resistance to several antibiotics, including penicillin ([≥]16 g/mL), ceftriaxone ([≥]32 g/mL), and meropenem ([≥]8 g/mL), which was caused by SHV-11 beta-lactamase, NDM-1 carbapenemase, and porin mutations (OmpK37, MdtQ). Yersiniabactin, enterobactin, and E. coli common pilus (ECP) genes were also present in the genome; these genes are essential for the acquisition of iron, adhesion, and immune evasion, among other virulence factors. kappa testing categorized the strain as K64 and O2a types. The presence of colicin genes, IncHI1B_1_pNDM-MAR and IncFIB replicons, and other plasmids in this strain demonstrate its ability to spread antibiotic resistance and facilitate horizontal gene transfer. Adding to its genetic variety and adaptability, the genome included CRISPR-Cas systems and eleven prophage regions. The 172,025 bp linear genome and 46.3% GC content of the N-15-like phage showed strong genomic similarities to phages of the Sugarlandvirus genus, especially those that infect K. pneumoniae. There were structural proteins (11.8 percent of ORFs), DNA replication and repair enzymes (9.3 percent of ORFs), and a toxin-antitoxin system (0.4 percent of ORFs) encoded by the phage genome. A protelomerase and ParA/B partitioning proteins indicate that the phage is replicating and maintaining itself in a manner similar to the N15 phage, which is renowned for maintaining a linear plasmid prophage throughout lysogeny. Lysogeny and horizontal gene transfer are two mechanisms by which phages may influence bacterial evolution. Learning about the phages role in bacterial evolution, host-phage relationships, and horizontal gene transfer is a great benefit. Understanding the dynamics of antibiotic resistance and pathogen development requires knowledge of phages like this one, which are known for their temperate nature and their function in altering bacterial virulence and resistance profiles. The regulatory and structural proteins of the phage also provide a model for research into the biology of temperate phages and their effects on microbial communities. The importance of temperate phages in bacterial genomes and their function in the larger framework of microbial ecology and evolution is emphasized in this research. Author SummaryAntibiotic-resistant bacteria represent a significant global health threat, and comprehending their interactions with bacteriophages is essential for formulating novel antimicrobial tactics and elucidating the molecular development of bacteria. This work examined an extensively drug-resistant (XDR) strain of Klebsiella pneumoniae isolated from an ICU patient and a temperate N-15-like phage identified in hospital effluent. The bacterial strain exhibited resistance to multiple antibiotics owing to an array of resistance genes, plasmids, porin mutations, and virulence characteristics that facilitated its survival and pathogenicity. The genomic investigation of the phage elucidated its structural organization, replication mechanisms, and possible contribution to bacterial development through lysogeny and horizontal gene transfer. Our findings underscore the intricate host-phage interactions that affect antibiotic resistance and pathogenicity in K. pneumoniae, offering significant insights into microbial evolution and the prospective relevance of phages in therapeutic approaches.

microbiology↗

Neoblast-like Stem Cells of Fasciola hepatica

The common liver fluke (Fasciola hepatica) causes the disease fasciolosis, which results in considerable losses within the global agri-food industry. There is a shortfall in the drugs that are effective against both the adult and juvenile life stages within the mammalian host, such that new drug targets are needed. Over the last decade the stem cells of parasitic flatworms have emerged as reservoirs of putative novel targets due to their role in development and homeostasis, including at host-parasite interfaces. Here, we investigate and characterise the proliferating cells that underpin development in F. hepatica. We provide evidence that these cells are capable of self-renewal, differentiation, and are sensitive to ionising radiation - all attributes of neoblasts in other flatworms. Changes in cell proliferation were also noted during the early stages of in vitro juvenile growth/development (around four to seven days post excystment), which coincided with a marked reduction in the nuclear area of proliferating cells. Furthermore, we generated transcriptomes from worms following irradiation-based ablation of neoblasts, identifying 124 significantly downregulated transcripts, including known stem cell markers such as fgfrA and plk1. Sixty-eight of these had homologues associated with neoblast-like cells in Schistosoma mansoni. Finally, RNA interference mediated knockdown of histone h2b (a marker of proliferating cells), ablated neoblast-like cells and impaired worm development in vitro. In summary, this work demonstrates that the proliferating cells of F. hepatica are equivalent to neoblasts of other flatworm species and demonstrate that they may serve as attractive targets for novel anthelmintics. Author SummaryLiver fluke are parasitic worms that infect both livestock and humans worldwide, threatening food security and human health. Treatments against this disease-causing parasite are limited, and growing resistance to drugs is undermining the effectiveness of control strategies. Since drugs represent the only viable control option, it is crucial that new drugs are discovered through the identification and validation of new drug targets. Stem cells play important roles in the normal growth and repair processes of many organisms, but when these cells become dysregulated through mutation, they can drive the development of cancers. Stem cells of liver fluke may be attractive novel drug targets as disruption would affect worm survival and/or development within their host. In this research we describe the characteristics of liver fluke stem cells, such as their sensitivity to radiation and their ability to develop into new cell types (key stem cell features). We used radiation in combination with RNA sequencing to identify genes associated with the liver fluke stem cells. Finally, we used reverse genetics to reduce the expression of a gene associated with stem cells, which led to the loss of stem cells and reduced worm growth/development. These data provide evidence to support the exploitation of stem cells as a source of novel drug targets for liver fluke control.

molecular biology↗