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Sharma M, Banday ZZ, Shukla BN, Laxmi A. Glucose-Regulated HLP1 Acts as a Key Molecule in Governing Thermomemory. Plant Physiol 2019; 180:1081-1100. [PMID: 30890662 PMCID: PMC6548265 DOI: 10.1104/pp.18.01371] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 03/04/2019] [Indexed: 05/04/2023]
Abstract
Induction of heat shock proteins (HSPs) in response to heat stress (HS) is indispensable for conferring thermotolerance. Glc, a fundamental signaling and metabolic molecule, provides energy to stressed seedlings to combat stress. The recovery of stressed plants from detrimental HS in response to Glc is largely mediated by HSPs, but the mechanistic basis of this thermotolerance is not well defined. In this study, we show that Glc has a prominent role in providing thermotolerance. Glc-mediated thermotolerance involves HSP induction via the TARGET OF RAPAMYCIN (TOR)-E2Fa signaling module. Apart from HSPs, TOR-E2Fa also regulates the Arabidopsis (Arabidopsis thaliana) ortholog of human Hikeshi, named HIKESHI-LIKE PROTEIN1 (HLP1). Expression of proHLP1::GUS in the shoot apical meristem (SAM) after HS coincides with TOR-E2Fa expression, substantiating a role for TOR-E2Fa-HLP1 in providing thermotolerance. We also demonstrate that Glc along with heat could induce proliferation activity in the SAM after HS recovery, which was arrested by the TOR inhibitor AZD-8055. Molecular and physiological studies suggest that HS-activated heat stress transcription factor A1s also positively regulate HLP1 transcription, suggesting convergence of the Glc and HS signaling pathways. Loss of functional HLP1 causes HS hypersensitivity, whereas HLP1 overexpressors display increased thermotolerance. HLP1 binds to the promoters of Glc-regulated HS-responsive genes and promotes chromatin acetylation. In addition, Glc modifies the chromatin landscape at thermomemory-related loci by promoting H3K4 trimethylation (H3K4me3). Glc-primed accumulation of H3K4me3 at thermomemory-associated loci is mediated through HLP1. These findings reveal the novel function of Glc-regulated HLP1 in mediating thermotolerance/thermomemory response.
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Affiliation(s)
- Mohan Sharma
- National Institute of Plant Genome Research, New Delhi-110067, India
| | | | | | - Ashverya Laxmi
- National Institute of Plant Genome Research, New Delhi-110067, India
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Jamsheer K M, Singh D, Sharma M, Sharma M, Jindal S, Mannully CT, Shukla BN, Laxmi A. The FCS-LIKE ZINC FINGER 6 and 10 are involved in regulating osmotic stress responses in Arabidopsis. Plant Signal Behav 2019; 14:1592535. [PMID: 30871406 PMCID: PMC6546138 DOI: 10.1080/15592324.2019.1592535] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The TARGET OF RAPAMYCIN-SNF1-RELATED PROTEIN KINASE 1 (TOR-SnRK1) arms race is a key regulator of plant growth in response to energy fluctuations and stress. Recently, we have identified that two members of the FCS-LIKE ZINC FINGER (FLZ) protein family, FLZ6 and 10, repress SnRK1 signaling and thereby involved in the activation of the TARGET OF RAPAMYCIN (TOR) signaling. In this study, we demonstrate that FLZ6 and 10 are also involved in the regulation of osmotic stress responses. Downregulation of FLZ6 and 10 results in enhanced expression of stress-responsive genes and better resilience towards osmotic stress at the seedling stage. These results indicate that FLZ6 and 10 are involved in the regulation of stress mitigation in plants through directly affecting SnRK1 signaling.
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Affiliation(s)
- Muhammed Jamsheer K
- National Institute of Plant Genome Research, New Delhi, India
- Amity Food & Agriculture Foundation, Amity University Uttar Pradesh, Noida, India
| | - Dhriti Singh
- National Institute of Plant Genome Research, New Delhi, India
| | - Mohan Sharma
- National Institute of Plant Genome Research, New Delhi, India
| | - Manvi Sharma
- National Institute of Plant Genome Research, New Delhi, India
| | - Sunita Jindal
- National Institute of Plant Genome Research, New Delhi, India
| | | | | | - Ashverya Laxmi
- National Institute of Plant Genome Research, New Delhi, India
- CONTACT Ashverya Laxmi National Institute of Plant Genome Research, Aruna Asaf Ali Road, Post Box No. 10531, New Delhi 110067, India
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Jamsheer K M, Shukla BN, Jindal S, Gopan N, Mannully CT, Laxmi A. The FCS-like zinc finger scaffold of the kinase SnRK1 is formed by the coordinated actions of the FLZ domain and intrinsically disordered regions. J Biol Chem 2018; 293:13134-13150. [PMID: 29945970 DOI: 10.1074/jbc.ra118.002073] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 06/05/2018] [Indexed: 11/06/2022] Open
Abstract
The SNF1-related protein kinase 1 (SnRK1) is a heterotrimeric eukaryotic kinase that interacts with diverse proteins and regulates their activity in response to starvation and stress signals. Recently, the FCS-like zinc finger (FLZ) proteins were identified as a potential scaffold for SnRK1 in plants. However, the evolutionary and mechanistic aspect of this complex formation is currently unknown. Here, in silico analyses predicted that FLZ proteins possess conserved intrinsically disordered regions (IDRs) with a propensity for protein binding in the N and C termini across the plant lineage. We observed that the Arabidopsis FLZ proteins promiscuously interact with SnRK1 subunits, which formed different isoenzyme complexes. The FLZ domain was essential for mediating the interaction with SnRK1α subunits, whereas the IDRs in the N termini facilitated interactions with the β and βγ subunits of SnRK1. Furthermore, the IDRs in the N termini were important for mediating dimerization of different FLZ proteins. Of note, the interaction of FLZ with SnRK1 was confined to cytoplasmic foci, which colocalized with the endoplasmic reticulum. An evolutionary analysis revealed that in general, the IDR-rich regions are under more relaxed selection than the FLZ domain. In summary, the findings in our study reveal the structural details, origin, and evolution of a land plant-specific scaffold of SnRK1 formed by the coordinated actions of IDRs and structured regions in the FLZ proteins. We propose that the FLZ protein complex might be involved in providing flexibility, thus enhancing the binding repertoire of the SnRK1 hub in land plants.
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Affiliation(s)
- Muhammed Jamsheer K
- From the National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi-110067 and
| | - Brihaspati N Shukla
- From the National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi-110067 and
| | - Sunita Jindal
- From the National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi-110067 and
| | - Nandu Gopan
- the Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru-560064, India
| | | | - Ashverya Laxmi
- From the National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi-110067 and
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Boliar S, Patil S, Shukla BN, Ghobbeh A, Deshpande S, Chen W, Guenaga J, Dimitrov DS, Wyatt RT, Chakrabarti BK. Ligand accessibility to the HIV-1 Env co-receptor binding site can occur prior to CD4 engagement and is independent of viral tier category. Virology 2018; 519:99-105. [PMID: 29684630 DOI: 10.1016/j.virol.2018.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 04/05/2018] [Accepted: 04/06/2018] [Indexed: 11/28/2022]
Abstract
HIV-1 virus entry into target cells requires the envelope glycoprotein (Env) to first bind the primary receptor, CD4 and subsequently the co-receptor. Antibody access to the co-receptor binding site (CoRbs) in the pre-receptor-engaged state, prior to cell attachment, remains poorly understood. Here, we have demonstrated that for tier-1 Envs, the CoRbs is directly accessible to full-length CD4-induced (CD4i) antibodies even before primary receptor engagement, indicating that on these Envs the CoRbs site is either preformed or can conformationally sample post-CD4-bound state. Tier-2 and tier-3 Envs, which are resistant to full-length CD4i antibody, are neutralized by m36.4, a lower molecular mass of CD4i-directed domain antibody. In some tier-2 and tier-3 Envs, CoRbs is accessible to m36.4 even prior to cellular attachment in an Env-specific manner independent of their tier category. These data suggest differential structural arrangements of CoRbs and varied masking of ligand access to the CoRbs in different Env isolates.
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Affiliation(s)
- Saikat Boliar
- THSTI-IAVI HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana 121001, India
| | - Shilpa Patil
- THSTI-IAVI HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana 121001, India
| | - Brihaspati N Shukla
- THSTI-IAVI HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana 121001, India
| | - Ali Ghobbeh
- IAVI Neutralizing Antibody Center at TSRI, Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Suprit Deshpande
- THSTI-IAVI HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana 121001, India
| | - Weizao Chen
- Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA
| | - Javier Guenaga
- IAVI Neutralizing Antibody Center at TSRI, Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Dimiter S Dimitrov
- Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA
| | - Richard T Wyatt
- IAVI Neutralizing Antibody Center at TSRI, Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | - Bimal K Chakrabarti
- THSTI-IAVI HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana 121001, India; IAVI Neutralizing Antibody Center at TSRI, Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA.
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Jamsheer K M, Sharma M, Singh D, Mannully CT, Jindal S, Shukla BN, Laxmi A. FCS-like zinc finger 6 and 10 repress SnRK1 signalling in Arabidopsis. Plant J 2018; 94:232-245. [PMID: 29406622 DOI: 10.1111/tpj.13854] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 01/05/2018] [Accepted: 01/17/2018] [Indexed: 05/14/2023]
Abstract
SNF1-related protein kinase 1 (SnRK1) is a central regulator of plant growth during energy starvation. The FCS-like zinc finger (FLZ) proteins have recently been identified as adaptor proteins which facilitate the interaction of SnRK1 with other proteins. In this study, we found that two starvation-induced FLZ genes, FLZ6 and FLZ10, work as repressors of SnRK1 signalling. The reduced expression of these genes resulted in an increase in the level of SnRK1α1, which is the major catalytic subunit of SnRK1. This lead to a concomitant increase in phosphorylated protein and SnRK1 activity in the flz6 and flz10 mutants. FLZ6 and FLZ10 specifically interact with SnRK1α subunits in the cytoplasmic foci, which co-localized with the endoplasmic reticulum. In physiological assays, similar to the SnRK1α1 overexpression line, flz mutants showed compromised growth. Further, growth promotion in response to favourable growth conditions was found to be attenuated in the mutants. The enhanced SnRK1 activity in the mutants resulted in a reduction in the level of phosphorylated RIBOSOMAL S6 KINASE and the expression of E2Fa and its targets, indicating that TARGET OF RAPAMYCIN-dependent promotion of protein synthesis and cell cycle progression is impaired. Taken together, this study uncovers a plant-specific modulation of SnRK1 signalling.
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Affiliation(s)
- Muhammed Jamsheer K
- National Institute of Plant Genome Research, Aruna Asaf Ali Road, New Delhi, 110067, India
| | - Manvi Sharma
- National Institute of Plant Genome Research, Aruna Asaf Ali Road, New Delhi, 110067, India
| | - Dhriti Singh
- National Institute of Plant Genome Research, Aruna Asaf Ali Road, New Delhi, 110067, India
| | - Chanchal T Mannully
- National Institute of Plant Genome Research, Aruna Asaf Ali Road, New Delhi, 110067, India
| | - Sunita Jindal
- National Institute of Plant Genome Research, Aruna Asaf Ali Road, New Delhi, 110067, India
| | - Brihaspati N Shukla
- National Institute of Plant Genome Research, Aruna Asaf Ali Road, New Delhi, 110067, India
| | - Ashverya Laxmi
- National Institute of Plant Genome Research, Aruna Asaf Ali Road, New Delhi, 110067, India
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Das S, Boliar S, Samal S, Ahmed S, Shrivastava T, Shukla BN, Goswami S, Bansal M, Chakrabarti BK. Identification and characterization of a naturally occurring, efficiently cleaved, membrane-bound, clade A HIV-1 Env, suitable for immunogen design, with properties comparable to membrane-bound BG505. Virology 2017; 510:22-28. [PMID: 28689085 DOI: 10.1016/j.virol.2017.07.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 06/29/2017] [Accepted: 07/02/2017] [Indexed: 10/19/2022]
Abstract
Efficient cleavage of HIV-1 Env gp160 into its constituent subunits correlates with selective binding to neutralizing antibodies and are the closest mimetic of native, functional Envs. This was first demonstrated with the clade B Env, JRFL. The correlation between efficient cleavage and selective binding to neutralizing antibodies is the guiding principle for immunogen design for HIV vaccine. We have recently reported that Envs 4-2.J41 (clade C) and JRCSF (clade B) are also efficiently cleaved and show similar properties. However, an efficiently cleaved, membrane-bound clade A Env suitable for genetic vaccination has not been directly demonstrated. Here we report that BG505 and a new clade A Env, QB726.70M.ENV.C4 (or A5) are efficiently cleaved on cell membrane. A5 shows desirable antigenic properties comparable with BG505 on cell surface. A5SOSIP in supernatant displays majority of bNAb binding epitopes. Thus, both BG505 and A5 Envs can be used in DNA prime-protein boost vaccination studies.
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Affiliation(s)
- Supratik Das
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 3rd Milestone, Faridabad-Gurgaon Expressway, PO box #04, Faridabad 121001, Haryana, India
| | - Saikat Boliar
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 3rd Milestone, Faridabad-Gurgaon Expressway, PO box #04, Faridabad 121001, Haryana, India
| | - Sweety Samal
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 3rd Milestone, Faridabad-Gurgaon Expressway, PO box #04, Faridabad 121001, Haryana, India
| | - Shubbir Ahmed
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 3rd Milestone, Faridabad-Gurgaon Expressway, PO box #04, Faridabad 121001, Haryana, India
| | - Tripti Shrivastava
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 3rd Milestone, Faridabad-Gurgaon Expressway, PO box #04, Faridabad 121001, Haryana, India
| | - Brihaspati N Shukla
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 3rd Milestone, Faridabad-Gurgaon Expressway, PO box #04, Faridabad 121001, Haryana, India
| | - Sandeep Goswami
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 3rd Milestone, Faridabad-Gurgaon Expressway, PO box #04, Faridabad 121001, Haryana, India
| | - Manish Bansal
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 3rd Milestone, Faridabad-Gurgaon Expressway, PO box #04, Faridabad 121001, Haryana, India
| | - Bimal K Chakrabarti
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 3rd Milestone, Faridabad-Gurgaon Expressway, PO box #04, Faridabad 121001, Haryana, India; IAVI Neutralizing Antibody Center at TSRI, La Jolla, CA, USA.
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7
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Boliar S, Das S, Bansal M, Shukla BN, Patil S, Shrivastava T, Samal S, Goswami S, King CR, Bhattacharya J, Chakrabarti BK. An efficiently cleaved HIV-1 clade C Env selectively binds to neutralizing antibodies. PLoS One 2015; 10:e0122443. [PMID: 25822521 PMCID: PMC4379091 DOI: 10.1371/journal.pone.0122443] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 02/13/2015] [Indexed: 12/18/2022] Open
Abstract
An ideal HIV-1 Env immunogen is expected to mimic the native trimeric conformation for inducing broadly neutralizing antibody responses. The native conformation is dependent on efficient cleavage of HIV-1 Env. The clade B isolate, JRFL Env is efficiently cleaved when expressed on the cell surface. Here, for the first time, we report the identification of a native clade C Env, 4-2.J41 that is naturally and efficiently cleaved on the cell surface as confirmed by its biochemical and antigenic characteristics. In addition to binding to several conformation-dependent neutralizing antibodies, 4-2.J41 Env binds efficiently to the cleavage-dependent antibody PGT151; thus validating its native cleaved conformation. In contrast, 4-2.J41 Env occludes non-neutralizing epitopes. The cytoplasmic-tail of 4-2.J41 Env plays an important role in maintaining its conformation. Furthermore, codon optimization of 4-2.J41 Env sequence significantly increases its expression while retaining its native conformation. Since clade C of HIV-1 is the prevalent subtype, identification and characterization of this efficiently cleaved Env would provide a platform for rational immunogen design.
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Affiliation(s)
- Saikat Boliar
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 496 Udyog Vihar, Phase-III, Gurgaon-122 016, Haryana, India
| | - Supratik Das
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 496 Udyog Vihar, Phase-III, Gurgaon-122 016, Haryana, India
| | - Manish Bansal
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 496 Udyog Vihar, Phase-III, Gurgaon-122 016, Haryana, India
| | - Brihaspati N. Shukla
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 496 Udyog Vihar, Phase-III, Gurgaon-122 016, Haryana, India
| | - Shilpa Patil
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 496 Udyog Vihar, Phase-III, Gurgaon-122 016, Haryana, India
| | - Tripti Shrivastava
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 496 Udyog Vihar, Phase-III, Gurgaon-122 016, Haryana, India
| | - Sweety Samal
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 496 Udyog Vihar, Phase-III, Gurgaon-122 016, Haryana, India
| | - Sandeep Goswami
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 496 Udyog Vihar, Phase-III, Gurgaon-122 016, Haryana, India
| | | | - Jayanta Bhattacharya
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 496 Udyog Vihar, Phase-III, Gurgaon-122 016, Haryana, India
| | - Bimal K. Chakrabarti
- THSTI-IAVI HIV Vaccine Design Program, Translational Health Science and Technology Institute, 496 Udyog Vihar, Phase-III, Gurgaon-122 016, Haryana, India
- * E-mail:
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Bhanumathi R, Sabeena F, Isac SR, Shukla BN, Singh DV. Molecular characterization of Vibrio cholerae O139 bengal isolated from water and the aquatic plant Eichhornia crassipes in the River Ganga, Varanasi, India. Appl Environ Microbiol 2003; 69:2389-94. [PMID: 12676727 PMCID: PMC154771 DOI: 10.1128/aem.69.4.2389-2394.2003] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A collection of ten strains of Vibrio cholerae O139, comprising six isolates from Eichhornia crassipes, two from water of the River Ganga, and one each from a well and a hand pump, were characterized. All the strains carried the CTX genetic element (ctxA, zot, and ace) except for the st gene and carried structural and regulatory genes for toxin-coregulated pilus (tcpA, tcpI, and toxR), adherence factor (ompU), and accessory colonization factor (acfB); all produced cholera toxin (CT). These strains were resistant to trimethoprim, sulfamethoxazole, streptomycin, and to the vibriostatic agent pteridine. Results obtained by ribotyping and enterobacterial repetitive intergenic consensus sequence-PCR fingerprint analysis indicate that multiple clones of toxigenic-pathogenic V. cholerae O139 were present in the aquatic environment.
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Affiliation(s)
- R Bhanumathi
- Rajiv Gandhi Centre for Biotechnology, Poojappura, Thiruvananthapuram 695 014, Kerala, India
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Sen MR, Shukla BN, Goyal RK. Seroprevalence of brucellosis in and around Varanasi. J Commun Dis 2002; 34:226-7. [PMID: 14703058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Affiliation(s)
- M R Sen
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi
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10
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Singh DV, Matte MH, Matte GR, Jiang S, Sabeena F, Shukla BN, Sanyal SC, Huq A, Colwell RR. Molecular analysis of Vibrio cholerae O1, O139, non-O1, and non-O139 strains: clonal relationships between clinical and environmental isolates. Appl Environ Microbiol 2001; 67:910-21. [PMID: 11157262 PMCID: PMC92666 DOI: 10.1128/aem.67.2.910-921.2001] [Citation(s) in RCA: 172] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A total of 26 strains of Vibrio cholerae, including members of the O1, O139, and non-O1, non-O139 serogroups from both clinical and environmental sources, were examined for the presence of genes encoding cholera toxin (ctxA), zonula occludens toxin (zot), accessory cholera enterotoxin (ace), hemolysin (hlyA), NAG-specific heat-stable toxin (st), toxin-coregulated pilus (tcpA), and outer membrane protein (ompU), for genomic organization, and for the presence of the regulatory protein genes tcpI and toxR in order to determine relationships between epidemic serotypes and sources of isolation. While 22 of the 26 strains were hemolytic on 5% sheep blood nutrient agar, all strains were PCR positive for hlyA, the hemolysin gene. When multiplex PCR was used, all serogroup O1 and O139 strains were positive for tcpA, ompU, and tcpI. All O1 and O139 strains except one O1 strain and one O139 strain were positive for the ctxA, zot, and ace genes. Also, O1 strain VO3 was negative for the zot gene. All of the non-O1, non-O139 strains were negative for the ctxA, zot, ace, tcpA, and tcpI genes, and all of the non-O1, non-O139 strains except strain VO26 were negative for ompU. All of the strains except non-O1, non-O139 strain VO22 were PCR positive for the gene encoding the central regulatory protein, toxR. All V. cholerae strains were negative for the NAG-specific st gene. Of the nine non-ctx-producing strains of V. cholerae, only one, non-O1, non-O139 strain VO24, caused fluid accumulation in the rabbit ileal loop assay. The other eight strains, including an O1 strain, an O139 strain, and six non-O1, non-O139 strains, regardless of the source of isolation, caused fluid accumulation after two to five serial passages through the rabbit gut. Culture filtrates of all non-cholera-toxigenic strains grown in AKI media also caused fluid accumulation, suggesting that a new toxin was produced in AKI medium by these strains. Studies of clonality performed by using enterobacterial repetitive intergenic consensus sequence PCR, Box element PCR, amplified fragment length polymorphism (AFLP), and pulsed-field gel electrophoresis (PFGE) collectively indicated that the V. cholerae O1 and O139 strains had a clonal origin, whereas the non-O1, non-O139 strains belonged to different clones. The clinical isolates closely resembled environmental isolates in their genomic patterns. Overall, there was an excellent correlation among the results of the PCR, AFLP, and PFGE analyses, and individual strains derived from clinical and environmental sources produced similar fingerprint patterns. From the results of this study, we concluded that the non-cholera-toxin-producing strains of V. cholerae, whether of clinical or environmental origin, possess the ability to produce a new secretogenic toxin that is entirely different from the toxin produced by toxigenic V. cholerae O1 and O139 strains. We also concluded that the aquatic environment is a reservoir for V. cholerae O1, O139, non-O1, and non-O139 serogroup strains.
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Affiliation(s)
- D V Singh
- Rajiv Gandhi Centre for Biotechnology, Jagathy, Thiruvananthapuram 695 014, India.
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Abstract
The synthesis of fifteen new 1-aryl-2-amino-3-(4-arylthiazol-2-yl)/(benzothiazol-2-yl)gua nidines is described. They were screened for their antimicrobial susceptibility by the standard disc diffusion method of the World Health Organization (WHO) and the activities compared with that of standard strain of Escherichia coli NCTC 10418. The sensitive aminoguanidines were further subjected to the minimum inhibitory concentration (MIC) test.
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Affiliation(s)
- R Lakhan
- Department of Chemistry, Banaras Hindu University, Varanasi, India
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12
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Abstract
In a hospital-based study, stool samples from 2095 patients of all ages were examined for different fungal, protozoal and bacterial enteropathogens over a period of 2 years (July 1994-June 1996). Cryptosporidium was detected in 151 specimens (7.2%) and was the third commonest pathogen found. The highest prevalence of this organism was in the group aged 16-45 years and during the rainy months (July-Oct.). Diarrhoea caused by the protozoon was of mild to moderate severity and features of dysentery were absent. Amongst other enteropathogens, Candida albicans was the most frequently isolated, followed by enteropathogenic and enterotoxigenic Escherichia coli, Salmonella spp., Campylobacter jejuni, Entamoeba histolytica, Giardia duodenalis (lamblia), Shigella spp., Vibrio cholerae and Aeromonas spp.
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Affiliation(s)
- Gopal Nath
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221 005, India
| | - A Choudhury
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221 005, India
| | - B N Shukla
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221 005, India
| | - T B Singh
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221 005, India
| | - D C S Reddy
- PSM, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221 005, India
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Shukla BN, Nath G, Chaudhury A, Sanyal SC. Vibrio cholerae O139 in the subcontinent. J Diarrhoeal Dis Res 1996; 14:214-5. [PMID: 9019018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Abstract
Of 28 isolates of Vibrio cholerae non-O1 (10 from diarrhoeal patients and 18 from environmental sources) examined for haemolytic activity and its correlation, if any, with enterotoxic activity, 24 showed haemolysis. The four non-haemolytic isolates showed haemolysis after consecutive passages through rabbit ileal loops (RILs). The titres of haemolytic activity were 4-64 HU/ml irrespective of their source. Eight (28.5%) of the non-O1 isolates caused fluid accumulation; six (25%) were haemolytic and two (50%) non-haemolytic. The remaining isolates showed enterotoxic activity after one-to-three consecutive passages through RILs irrespective of their haemolytic character and source. Environmental isolates caused significantly more fluid accumulation than the diarrhoeal isolates. All these isolates reverted to their original non-toxigenic character on repeated subculture or on storage in the laboratory, but continued to show haemolytic activity. The results of the present study indicate that V. cholerae non-O1 strains are potentially enterotoxigenic independent of their haemolytic character and source, and enterotoxin, not haemolysin, is the factor most likely to be responsible for their enterotoxic activity.
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Affiliation(s)
- D V Singh
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
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Chaudhury A, Nath G, Shukla BN, Sanyal SC. Biochemical characterisation, enteropathogenicity and antimicrobial resistance plasmids of clinical and environmental Aeromonas isolates. J Med Microbiol 1996; 44:434-7. [PMID: 8636960 DOI: 10.1099/00222615-44-6-434] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
One hundred and eight strains of Aeromonas from clinical and environmental samples were speciated. Seven species were identified, the most prevalent of which was A. hydrophila. Experimental studies in an animal model with 36 representative strains of different species revealed that all strains could cause significant fluid accumulation in rabbit ileal loops. Of 107 strains showing single or multiple antimicrobial resistance, the highest incidence of resistance was shown for beta-lactam antibiotics other than cefotaxime. Transferable resistance plasmids, encoding resistance to ampicillin, cephalexin, cefoxitin, erythromycin and furazolidone, either alone or in combination, were detected in 35 strains. A further proportion of strains could be cured of one or more resistance markers, including resistance to nalidixic acid, and this was accompanied by the loss of plasmid DNA. The plasmids ranged in size between 85.6 and > 1 50 kb.
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Affiliation(s)
- A Chaudhury
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
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Tikoo A, Singh DV, Shukla BN, Sanyal SC. Development of an improved synthetic medium for a better production of the new cholera toxin and its immunological relationship with the toxin produced by Vibrio cholerae O139 strains. FEMS Immunol Med Microbiol 1996; 14:67-72. [PMID: 8809541 DOI: 10.1111/j.1574-695x.1996.tb00272.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
An improved synthetic medium (M4) comprising syncase medium supplemented with sodium chloride (1%) and sucrose (0.5%) pH adjusted to 7.4 was developed for a better production of the new cholera toxin (NCT). The culture filtrates prepared in the M4 medium caused significantly (P > 0.05) more fluid accumulation than that in syncase medium. Crude toxin, prepared in the M4 medium with V. cholerae O1 strains (X-392 and 2740-80) caused a reaction similar to that of the same amount of NCT (32 micrograms) prepared in the syncase medium. The neutralization of the optimal loop reacting dose of the NCT prepared in the M4 medium by anti-NCT raised against syncase prepared toxin indicates the release of the same kind of toxin in both media. These observations indicate that the modified M4 medium may be used for NCT preparation and further characterization. All the strains of Vibro cholerae O139 used in this study produced a toxin antigenically similar to NCT.
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Affiliation(s)
- A Tikoo
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
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Shukla BN, Singh DV, Sanyal SC. Attachment of non-culturable toxigenic Vibrio cholerae O1 and non-O1 and Aeromonas spp. to the aquatic arthropod Gerris spinolae and plants in the River Ganga, Varanasi. FEMS Immunol Med Microbiol 1995; 12:113-20. [PMID: 8589660 DOI: 10.1111/j.1574-695x.1995.tb00182.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Non-cultivable, pathogenic O1 and non-O1 Vibrio cholerae and Aeromonas spp. were resuscitated from aquatic arthropods and plant homogenate respectively, by rabbit ileal loop (RIL) assay. These organisms adhered to the aquatic arthropod Gerris spinolae and various species of phytoplankton in the River Ganga, but failed to grow after direct inoculation on artificial media except for only 10 homogenates of the arthropod. The number of non-O1 V. cholerae and Aeromonas recovered on direct inoculation of G. spinolae homogenates were in the order of 10(5)-10(6) whereas those of the Ganga water were 10(2)-10(3) ml-1. A total of 119 strains of O1 and non-O1 V. cholerae and Aeromonas spp. (69 isolates from G. spinolae and 50 from aquatic plants) were recovered from the loop contents. The results indicate that production of the enzyme chitinase by O1 and non-O1 V. cholerae and Aeromonas spp. might facilitate their adsorption and multiplication on different species of zoo- and phyto-plankton. Most of the isolates were enterotoxic, haemolytic and resistant to different antibiotics. This study suggests that species of zoo- and phyto-planktons, until now not reported to be associated with O1 and non-O1 V. cholerae, may act as reservoirs of these organisms as well as different species of Aeromonas in a fresh-water riverine ecosystem.
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Affiliation(s)
- B N Shukla
- Department of Microbiology, Banaras Hindu University, Varanasi, India
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Nath G, Shukla BN, Reddy DC, Sanyal SC. A community study on the aetiology of childhood diarrhoea with special reference to Campylobacter jejuni in a semiurban slum of Varanasi, India. J Diarrhoeal Dis Res 1993; 11:165-8. [PMID: 8263306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In a community study of 607 diarrhoeal and 529 non-diarrhoeal (control) patients less than 5 years old carried out between August 1988 and July 1989, the Campylobacter jejuni isolation rate was 4% in the diarrhoeal and 0.9% in the control group. It was the second most common bacterial enteropathogen isolated after Escherichia coli. Its incidence was more common among 1-2 year old children (4.8%) and during rainy season (July-October). Features of dysentery were absent in C. jejuni diarrhoea. Findings strongly suggest its aetiological role in childhood diarrhoea. Among other enteropathogens in diarrhoeal specimens, rotavirus was the commonest (16.4%) followed by enterotoxigenic E. coli (13.8%), G. lamblia (10.3%), enteropathogenic E. coli (7.0%), E. histolytica (5.0%), Cryptosporidium (3.8%), H. nana spp. (1.5%), NAG vibrios (0.5%), P. shigelloides (0.5%), V. mimicus and Salmonella spp. (0.3%). Approximately one quarter of the stool specimens (22.6%, 256/1136) tested were positive for the ova of A. lumbricoides.
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Affiliation(s)
- G Nath
- Department of Microbiology, Banaras Hindu University, Varanasi, India
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Shukla BN, Agarwal RK, Sanyal SC. Isolation of Campylobacter spp from the river Ganga in Varanasi. Indian J Med Res 1988; 87:216-20. [PMID: 3397155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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