Pyridine appended pyrimidine bis hydrazone: Zn2+/ATP detection, bioimaging and functional properties of its dinuclear Zn(II) complex.

A pyridine functionalized pyrimidine-based system, H2P was successfully synthesized, characterized, and evaluated for its remarkable selective characteristics towards Zn2+ and ATP ions. The chemical sensing capabilities of H2P were demonstrated through absorption, fluorescence, and NMR spectroscopic techniques. The probe exhibited outstanding sensitivity when interacting with the ions, demonstrating relatively strong association constants and impressively low detection limits. The comprehensive binding mechanism of H2P with respect to Zn2+ and ATP ions was investigated using a combination of analytical methods, including Job's plot, NMR spectroscopy, mass spectrometry, and density functional theory (DFT) experiments. The interesting sensing ability of H2P for Zn2+/ATP ions was harnessed for live cell bioimaging and other diverse on-site detection purposes, including paper strips, cotton swabs, and applications involving mung bean sprouts. Further, the fluorescent probe demonstrated its effectiveness in detecting Zn2+ and ATP within live cells, indicating its significant potential in the realm of biological imaging applications. Moreover, the molecular configuration of the zinc complex (H2P-Zn2Cl4), derived from H2P, was elucidated using X-ray crystallography. This complex exhibited intriguing multifunctional attributes, encompassing its capability for detecting picric acid and for reversible acid/base sensing responses. The enhanced conducting behavior of the complex as well as its resistance properties were investigated by performing I-V characteristics and electrochemical impedance spectroscopic (EIS) experiments respectively.

Genetic diversity of cucumber green mottle mosaic virus (CGMMV) infecting cucurbits.

Cucumber green mottle mosaic virus (CGMMV), a well-known Tobamovirus, infects cucurbits across the globe. To determine its current status, molecular characterization, genetic recombination, gene flow and selection pressure, 10 districts from Punjab province of Pakistan were surveyed and a total of 2561 cucurbits samples were collected during 2019-2020. These samples were subjected to virus-specific double antibody sandwich-enzyme linked immunosorbent assay (DAS-ELISA) for the detection of CGMMV. The results revealed that viral disease was prevalent in all surveyed districts of Punjab with an overall 25.69% disease incidence. ELISA positive samples were further confirmed through RT-PCR and sequencing of coat protein (CP) cistron. Sequence analysis showed that the present studied CGMMV isolates have 96-99.5% nucleotide and 94.40-99.50% amino acid identities with those already available in GenBank. Phylogenetic analysis also revealed that understudied isolates were closely related with South Korean (AB369274) and Japanese (V01551) isolates and clustered in a separate clad. Sequence polymorphisms were observed in 663 bp of sequence within 31 CGMMV isolates covering complete CP gene. Total number of sites were 662, of which 610 and 52 sites were monomorphic and polymorphic (segregating), respectively. Of these polymorphic, 24 were singleton variable and 28 were parsimony informative. Overall nucleotide diversity (π) in all the understudied 31 isolates was 0.00010 while a total of 1 InDel event was observed and InDel Diversity (k) was 0.065. Haplotype diversity analysis revealed that there was a total 29 haplotypes with haplotype diversity (Hd) of 0.993458 in all the 31 isolates which provide evidence of less diversity among Pakistani isolates. The statistical analysis revealed the values 2.568, 5.31304 and 4.86698 of Tajima's D, Fu, & Li's F* and D*, respectively, which witnessed the population of CGMMV was under balanced selection pressure.