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Biology subjects

Hui, Z.

Publications and source records attributed to Hui, Z..

5 recordsLinked to original sources

Morphological Identification of Ticks in district Swabi, Mardan, and Charsadda

Ticks are ectoparasitic arthropods that play a significant role in transmitting pathogens to humans and animals. This study aimed to address the research gap in understanding the morphological diversity and distribution of tick species in Swabi, Mardan, and Charsadda districts of Pakistan, where tick-borne diseases are prevalent but poorly documented. The primary objectives were to identify tick species, document their morphological characteristics, and map their distribution patterns across different habitats. Field surveys were conducted over nine months, collecting tick specimens from forests, grasslands, and residential areas. Specimens were preserved and analyzed using stereo-zoom microscopy and taxonomic keys for accurate classification. Key findings revealed a diverse tick fauna, including hard ticks (Ixodidae), with variations in body size, colour patterns, capitulum shape, and scutum features. Some species were widely distributed across all three districts, while others exhibited localized patterns. The study provides the first comprehensive morphological identification of tick species in these regions, highlighting their potential role in disease transmission. The implications of this research are significant for public health and disease control. The data can inform targeted interventions, enhance disease surveillance programs, and support the development of preventive measures to mitigate tick-borne diseases. By contributing to tick taxonomy and epidemiology, this study lays the groundwork for protecting public health in the study regions and beyond. This study addresses the lack of data on tick diversity in high-prevalence regions of Pakistan, providing critical insights for disease control and public health strategies. Limited information exists on the morphological diversity and distribution of tick species in Swabi, Mardan, and Charsadda districts. To identify tick species, document morphological characteristics, and map their distribution patterns in the study areas. Field surveys, specimen collection, stereo-zoom microscopy, and taxonomic classification were employed over nine months. Diverse tick fauna was identified, including hard ticks, with variations in morphology and distribution. Some species were widespread, while others were localized, highlighting potential disease transmission risks. The findings support targeted interventions, disease surveillance, and preventive measures, contributing to public health protection and tick-borne disease control in the region.

zoology↗

Integration of microbial and chemical synthesis for the efficient production of plitidepsin, a promising anticancer and antiviral agent

Plitidepsin, a marine-derived anticancer medicine, is being tested in phase III clinical trials for treating COVID-19. However, the current supply of plitidepsin relies on laborious chemical synthesis processes. Here, we present a new approach that combines microbial and chemical synthesis to produce plitidepsin. We screened a Tistrella strain library to identify a high-yield didemnin B producer, and then introduced a second copy of the didemnin biosynthetic gene cluster into its genome, resulting in the highest yield of didemnin B reported in the literature. Next, we developed two straightforward chemical strategies to convert didemnin B to plitidepsin, one of which involved a one-step synthetic route giving over 90% overall yield. We also synthesized two new didemnin analogues and assessed their anticancer and antiviral activities. Our findings offer a practical and sustainable solution for producing plitidepsin and its derivatives, potentially expediting didemnin drug development.

synthetic biology↗

The N-glycosylation sites and Glycan-binding ability of S-protein in SARS-CoV-2 Coronavirus

The emerging acute respiratory disease, COVID-19, caused by SARS-CoV-2 Coronavirus (SARS2 CoV) has spread fastly all over the word. As a member of RNA viruses, the glycosylation of envelope glycoprotein plays the crucial role in protein folding, evasing host immune system, invading host cell membrane, even affecting host preference. Therefore, detail glyco-related researches have been adopted in the Spike protein (S-protein) of SARS2 CoV from the bioinformatic perspective. Phylogenic analysis of S-protein sequences revealed the evolutionary relationship of N-glycosylation sites in different CoVs. Structural comparation of S-proteins indicated their similarity and distributions of N-glycosylation sites. Further potential sialic acid or galactose affinity domains have been described in the S-protein by docking analysis. Molecular dynamic simulation for the glycosylated complexus of S-protein-ACE2 implied that the complicate viral binding of receptor-binding domain may be influenced by peripheric N-glycans from own and adjacent monoers. These works will contribute to investigate the N-glycosylation in S-protein and explain the highly contagious of COVID-19.

evolutionary biology↗

Identification of a peroxidase inhibitor that enhances kanamycin activity

BackgroundThe threat of antimicrobial resistance calls for more efforts in basic science, drug discovery, and clinical development, particularly gram-negative carbapenem-resistant pathogens. Objectives and methodsWhole-cell-based screening was performed to identify novel antibacterial agents against Acinetobacter baumannii ATCC19606. Spontaneously resistant mutant selection, whole-genome sequencing, and surface plasmon resonance were used for target identification and confirmation. Checkerboard titration assay was used for drug combination analysis. ResultsA small molecule named 6D1 with the chemical structure of 6-fluorobenzo[d]isothiazol-3(2H)-one was identified and exhibited activity against A. baumannii ATCC19606 strain (minimal inhibitory concentration, MIC = 1 mg/L). The mutation in the plasmid-derived ohrB gene that encodes a peroxidase was identified in spontaneously resistant mutants. Treatment of the bacteria with 6D1 resulted in increased sensitivity to peroxide such as tert-butyl hydroperoxide. The binding of 6D1 and OhrB was confirmed by surface plasmon resonance. Interestingly, the MIC of kanamycin against spontaneously resistant mutants decreased. Finally, we identified the effect of 6D1 on enhancing the antibacterial activity of kanamycin, including New Delhi metallo-{beta}-lactamase (NDM-1)-producing carbapenem-resistant Klebsiella pneumoniae, but not in strains carrying kanamycin resistance genes. ConclusionsIn this study, we identified a peroxidase inhibitor that suppresses the growth of A. baumannii and enhances the antibacterial activity of kanamycin. We propose that peroxidase may be potentially used as a target for kanamycin adjuvant development.

microbiology↗

A Novel Non-hypermucoviscous ST11 Hypervirulent Carbapenem-resistant Klebsiella pneumoniae Lacking Classical Virulence Factors

BackgroundHypervirulent Klebsiella pneumoniae lacking classical virulence factors is uncommon, and the virulence mechanisms of this organism are not understood. MethodsFollowing a retrospective study of carbapenem-resistant K. pneumoniae based on core genome multilocus sequence typing (cgMLST), isolates that caused high mortality were investigated with a genome-wide association study (GWAS), proteome analysis and an animal model. ResultsThe sublineage of sequence type 11 (ST11) K. pneumoniae, which belongs to complex type 3176 (CT3176) and K-locus 47 (KL47), was highlighted due to the high mortality of infected patients. GWAS analysis showed that ampR was associated with the CT3176 isolates. In a mouse model, the mortality of ampR-carrying isolates was comparable to that of the typical hypervirulent isolate GM2. Even during the first 24 hours of infection, the bacterial load and pathological changes of the ampR-carrying isolates in the lungs were more severe than those of GM2. The ampR complement mutant was able to enhance the virulence of the KL47 isolate but not the virulence of KL1. Proteome analysis showed that the expression of WcaJ in the ampR+ isolates was significantly higher than that in the ampR- isolates, and this result was also confirmed by transcription tests and capsule staining. It is suggested that the enhancement of the initial stage of capsule synthesis may be the cause of the high virulence of these non-hypermucoviscous ST11 carbapenem-resistant K. pneumoniae isolates. ConclusionsNon-hypermucoviscous ST11 hypervirulent carbapenem-resistant K. pneumoniae warrants continued surveillance and investigation.

microbiology↗