Begomovirus and DNA-satellites association with mosaic and leaf curl disease of Solanum nigrum and Physalis minima: the new hosts for chilli leaf curl virus.

The numerous plants of Solanum nigrum L, and Physalis minima L, well-known weeds with medicinal properties in agriculture and horticulture crops exhibiting severe mosaic, enation and leaf curl symptoms, were collected from the Varanasi and Mirzapur districts of Uttar Pradesh, India. The begomovirus infection in S. nigrum and P. minima was validated by PCR using virus-specific primers. The whole genome of the represented isolate of S. nigrum (SN1), P. minima (PM1), and beta satellite was amplified, cloned and sequenced. The SDT analysis showed that the DNA-A of PM1 and SN1 isolate showed the highest nt identity of 87.4 to 99.1%, with several chilli leaf curl virus (ChiLCuV) isolates from India and Oman, respectively. The betasatellite sequence (PM1ß) obtained from the PM1 isolate showed a very low identity of 83.1-84.5%. A demarcation threshold of 91% for betasatellite species delineation has led to identifying a new betasatellite in the PM1 sample. This unique betasatellite has been named "physalis minima leaf curl betasatellite," indicating its novelty with the plant. Whereas, betasatellite sequence (SN1ß) obtained from the SN1 sample showed 86.8-91.2% nucleotide identity with ChiLCB isolates infecting several crops in Indian subcontinents. The RDP analysis of the viral genome and betasatellite of SN1 and PM1 isolates revealed recombination in substantial portions of their genetic makeup, which appeared to have originated from pre-existing begomoviruses known to infect diverse host species. The present research also highlights the potential role of these plants as significant reservoir hosts for ChiLCuV in chili plants. Supplementary Information: The online version contains supplementary material available at 10.1007/s13337-023-00850-x.

Genome sequencing of cucumber mosaic virus (CMV) isolates infecting chilli and its interaction with host ferredoxin protein of different host for causing mosaic symptoms.

Chilli (Capsicum annuum L.) is an important vegetable crop grown in the Indian sub-continent and is prone to viral infections under field conditions. During the field survey, leaf samples from chilli plants showing typical symptoms of disease caused by cucumber mosaic virus (CMV) such as mild mosaic, mottling and leaf distortion were collected. DAC-ELISA analysis confirmed the presence of CMV in 71 out of 100 samples, indicating its widespread prevalence in the region. Five CMV isolates, named Gu1, Gu2, BA, Ho, and Sal were mechanically inoculated onto cucumber and Nicotiana glutinosa plants to study their virulence. Inoculated plants expressed the characteristic symptoms of CMV such as chlorotic spots followed by mild mosaic and leaf distortion. Complete genomes of the five CMV isolates were amplified, cloned, and sequenced, revealing RNA1, RNA2, and RNA3 sequences with 3358, 3045, and 2220 nucleotides, respectively. Phylogenetic analysis classified the isolates as belonging to the CMV-IB subgroup, distinguishing them from subgroup IA and II CMV isolates. Recombination analysis showed intra and interspecific recombination in all the three RNA segments of these isolates. In silico protein-protein docking approach was used to decipher the mechanism behind the production of mosaic symptoms during the CMV-host interaction in 13 host plants. Analysis revealed that the production of mosaic symptoms could be due to the interaction between the coat protein (CP) of CMV and chloroplast ferredoxin proteins. Further, in silico prediction was validated in 13 host plants of CMV by mechanical sap inoculation. Twelve host plants produced systemic symptoms viz., chlorotic spot, chlorotic ringspot, chlorotic local lesion, mosaic and mild mosaic and one host plant, Solanum lycopersicum produced mosaic followed by shoestring symptoms. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03777-8.

Molecular characterization of novel bipartite begomovirus associated with enation leaf disease of Garden croton (Codiaeum variegatum L.).

Garden croton (Codiaeum variegatum L.) plants showing typical begomovirus symptoms of vein twisting, enation and curling were collected from different gardens at Varanasi, Uttar Pradesh state of India ranged from 20 to 30%. All the 10 ten (CR1-CR10) infected samples of garden croton resulted in expected amplicon of 1.2 Kb in PCR specific to begomoviruses. No amplification was obtained for betasatellite and alphasatellite specific primers. The complete genome sequence of DNA-A and DNA-B for two isolates (CR1 and CR2) was obtained through rolling cycle amplification (RCA) and comparisons were made with other begomoviruses using Sequence Demarcation Tool (SDT) which revealed that, DNA-A of two isolates, CR1 (Acc.No.: MW816855) and CR2 (Acc.No.: MW816856) showed maximum nucleotide (nt) identity of 85.7-85.9% with Tomato leaf curl Karnataka virus, which is below the threshold percentage of begomovirus species demarcation, hence considered as novel begomovirus and proposed the name Garden croton enation leaf curl virus (CroELCuV) [IN: Varanasi: Croton: 18]. Further, DNA-B these isolates shared maximum nt identity of 91.0-92.2% (DNA-B) with Tomato leaf curl New Delhi virus. Recombination and GC plot analysis showed that the recombination occured at in low GC content regions of DNA-A and DNA-B of the CroELCuV and are derived from the previously reported several begomoviruses. This is the first record of novel bipartite begomovirus associated with vein twisting, enation and leaf curling of disease of garden garden croton in India and world. Supplementary Information: The online version contains supplementary material available at 10.1007/s13337-022-00772-0.

Oxalobacter formigenes: A new hope as a live biotherapeutic agent in the management of calcium oxalate renal stones.

Recent advances in understanding the association of gut microbiota with the host have shown evidence of certain bacterial therapeutic potentiality in preventing and treating metabolic diseases. Hyperoxaluria is a severe challenge in nephrology and has led to the novel gut eubiosis as current therapy. The human gut commensal, obligate anaerobic, and intestinal oxalate-degrading strains of Oxalobacter formigenes have drawn a promising significant interest for the next-generation probiotics (NGPs). This nonpathogenic, potential probiotic, and specialist oxalotrophic properties of O. formigenes give a new hope as a live biotherapeutic agent for calcium oxalate renal therapy. Numerous satisfactory outcomes of in vitro and in vivo studies were achieved on evaluating O. formigenes functionality, but the commercial production of this bacterium is yet to be achieved. This bacterium finds diverse application in dietary and endogenous oxalate degradation and the improvement of gut health, on which we concentrated our attention in this review. The relationship between good anaerobic gut bacterial dysbiosis and renal complications is comprehensively discussed to address the need for the development probiotic formulation. However, the commercial production of this bacteria on a broad scale is complex, with numerous obstacles, mainly because they are oxygen-sensitive and difficult to culture. This review will coherently present the current and available methodologies in producing, stabilizing, and delivering these NGPs to treat calcium stones. Moreover, the study presents the extensive work and key milestones achieved in the research on O. formigenes from tale to the truth.

Transmission, characterization and occurrence of recombination in Indian strain of squash leaf curl China virus associated with yellow mosaic and leaf curl disease of Summer squash.

Summer squash is one of the important vegetable crops and its production is hampered by various abiotic and biotic stresses. Of the different biotic stresses, viral infections are responsible for causing great losses to this crop. Diseases caused by begomoviruses are becoming a major constraint in the cultivation of summer squash. Samples from summer squash plants exhibiting severe yellow mosaic and leaf curl symptoms were collected from the Varanasi district of Uttar Pradesh (India) and begomovirus associated with these plants was transmitted through whiteflies (Bemisia tabaci) to healthy squash plants. The relationship between causal virus and whitefly vector was determined. The minimum acquisition access period (AAP) and inoculation feeding period (IFP) required by B. tabaci to transmit the virus was determined to be 10 min and female insects have greater efficiency in transmitting virus than male insects. The partial genome of the virus was amplified by PCR (1.2 kb), cloned and sequenced from the ten infected plant samples collected from field. Partial genome sequence analysis (1.2 kb) obtained from the ten samples revealed that they are associated with begomovirus species closely related to the Indian strain of Squash leaf curl China virus (SLCCNV). Therefore, one representative sample (Sq-1) was selected and complete genome of the virus was amplified by rolling circle amplification (RCA) method. Sequence analysis by Sequence Demarcation Tool (SDT) showed that the current isolate has maximum nucleotide (nt) identity of 93.7-98.4% and 89-98.1% with respect to DNA A DNA B, respectively with Indian strains of SLCCNV infecting cucurbits in India. Recombination analysis of genomes (DNA A and DNA B components) showed that a major part of genomes likely to be originated from already known begomoviruses (ToLCNDV, SLCCNV-CN and SLCCNV-IN) are infecting cucurbitaceous crops. Serological assays such as triple antibody sandwich-enzyme-linked immune-sorbent (TAS-ELISA) assay, dot blot immunobinding assay (DIBA), immuno-capture polymerase chain reaction (IC-PCR) were developed for the detection of SLCCNV. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02821-9.

In silico docking analysis revealed the potential of phytochemicals present in Phyllanthus amarus and Andrographis paniculata, used in Ayurveda medicine in inhibiting SARS-CoV-2.

The Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has resulted in outbreak of global pandemic, fatal pneumonia in human referred as Coronavirus Disease-2019 (Covid-19). Ayurveda, the age old practice of treating human ailments in India, can be considered against SARS-CoV-2. Attempt was made to provide preliminary evidences for interaction of 35 phytochemicals from two plants (Phyllanthus amarus and Andrographis paniculata used in Ayurveda) with SARS-CoV-2 proteins (open & closed state S protein, 3CLpro, PLpro and RdRp) through in silico docking analysis. The nucleotide analogue remdesivir, being used in treatment of SARS-CoV-2, was used as a positive control. The results revealed that 18 phytochemicals from P. amarus and 14 phytochemicals from A. paniculata shown binding energy affinity/dock score < - 6.0 kcal/mol, which is considered as minimum threshold for any compound to be used for drug development. Phytochemicals used for docking studies in the current study from P. amarus and A. paniculata showed binding affinity up to - 9.10 kcal/mol and - 10.60 kcal/mol, respectively. There was no significant difference in the binding affinities of these compounds with closed and open state S protein. Further, flavonoids (astragalin, kaempferol, quercetin, quercetin-3-O-glucoside and quercetin) and tannins (corilagin, furosin and geraniin) present in P. amarus have shown more binding affinity (up to - 10.60 kcal/mol) than remdesivir (up to - 9.50 kcal/mol). The pharmacokinetic predictions suggest that compounds from the two plants species studied in the current study are found to be non-carcinogenic, water soluble and biologically safe. The phytochemicals present in the extracts of P. amarus and A. paniculata might have synergistic effect with action on multiple target sites of SARS-CoV-2. The information generated here might serve as preliminary evidence for anti SARS-CoV-2 activity of phytochemicals present from P. amarus and A. paniculata and the potential of Ayurveda medicine in combating the virus. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-020-02578-7.