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1.
J Virol Methods ; 300: 114368, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34808229

RESUMEN

Narcissus (Narcissus tazetta) is a bulbous ornamental plant propagated vegetatively from bulbs. The Cyrtanthus elatus virus-A (CyEV-A) had been reported to cause a severe mosaic and yellow stripe disease in narcissus. Therefore, this study aimed to develop a protocol for the elimination of CyEV-A from infected bulblets by in vitro chemotherapy (30-50 mg/L ribavirin for 30 days) and electrotherapy (10-30 mA for 20 min), individually and in combination, to produce virus-free plants. The regenerated plants obtained from these treatments were screened for the absence of the CyEV-A by reverse-transcription polymerase chain reaction assays using a set of degenerate primers specific for a potyvirus coat protein gene. The results showed that in vitro chemotherapy (30 mg/L ribavirin for 30 days) alone produced 46.0 % (14/30) of virus-free plants, while electrotherapy (20 mA for 20 min) alone produced 40.0 % (12/30) of virus-free plants. In comparison, a combination of chemotherapy (30 mg/L ribavirin for 30 days) and electrotherapy (20 mA for 20 min) produced 50.0 % (15/30) of virus-free plants. The virus-free plants obtained from this combination treatment exhibited better growth and produced more bulbs compared to the other treatments and control. The protocol may be used for the control of the virus disease in narcissus.


Asunto(s)
Terapia por Estimulación Eléctrica , Narcissus , Potyvirus , Cartilla de ADN , Raíces de Plantas , Potyvirus/genética
2.
3 Biotech ; 9(11): 409, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31692678

RESUMEN

The complete genome sequence of Narcissus yellow stripe potyvirus (NYSV) isolated from Narcissus tazetta cv. Paperwhite exhibiting leaf chlorotic stripe symptoms was determined for the first time from India. The viral genome sequence contained 9650 nucleotides that encode a large polyprotein (372.36 kDa) of 3103 amino acids. The comparison of the NYSV genome sequences with corresponding sequences of other potyviruses revealed 90-97% identities and closest phylogenetic relationships with NYSV-Zhangzhou-1 and -ZZ-2 isolates infecting N. tazetta reported from China. Therefore, the NYSV isolate understudy was considered as a new member of NYSV and designated as NYSV-NAR2.

3.
Chemosphere ; 208: 626-639, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29894964

RESUMEN

Metallurgical exploitation originates metal-rich by-products termed slags, which are often disposed in the environment being a source of heavy metal pollution. Despite the environmental risk that this may pose for living organisms, little is known about the impact of slags on biotic components of the ecosystem like plants and rhizosphere microbial communities. In this study, metal-rich (Cu, Pb, Zn) granulated slags (GS) derived from Cu production process, were used for a leaching test in the presence of the soil pore solution, showing that soil solution enhanced the release of Cu from GS. A pot experiment was conducted using as growing substrate for sunflower (Helianthus annuus) a 50% w/w mix of an agricultural soil and GS. Bioavailability of metals in soil was, in increasing order: Pb < Zn < Cu. Sunflower was able to grow in the presence of GS and accumulated metals preferentially in above-ground tissues. Microbial diversity was assessed in rhizosphere and bulk soil using community level physiological profiling (CLPP) and 16S rRNA gene based denaturing gradient gel electrophoresis (DGGE) analyses, which demonstrated a shift in the diversity of microbial communities induced by GS. Overall, these results suggest that metallurgical wastes should not be considered inert when dumped in the soil. Implications from this study are expected to contribute to the development of sustainable practices for the management of pyrometallurgical slags, possibly involving a phytomanagement approach.


Asunto(s)
Ecosistema , Helianthus/metabolismo , Metalurgia/métodos , Metales Pesados/análisis , Rizosfera , Biodegradación Ambiental , Contaminación Ambiental/análisis , Helianthus/crecimiento & desarrollo , Helianthus/microbiología , Suelo/química
4.
3 Biotech ; 8(3): 168, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29527455

RESUMEN

Narcissus tazetta L. is a bulbous ornamental plant popular for its notable fragrant flowers which make it the plant of high importance. In spite of its economic value, narcissus is found to be susceptible for a number of diseases borne by fungi, bacteria, nematodes, and viruses. A potyvirus, Cyrtanthus elatus virus-A isolate NBRI16 (CEVA-NBRI16), associated with leaf chlorotic stripe disease of N. tazetta cv. Paperwhite was reported for first time in India from our laboratory based on the partial coat protein gene sequence. In present study, the full-length genomic sequence of CEVA-NBRI16 is determined which consists of 9942 nucleotides, excluding the polyA tail, and encodes a single large polyprotein of 3102 amino acids with the genomic features typical of a potyvirus. It shares highest 93% nucleotide sequence identity and closest phylogenetic relationship with sequences of CEVA-Marijiniup7-1 and CEVA-Marijiniup7-2, both reported from Australia on Cyrtanthus elatus host. The full-length genomic sequence of CEVA from narcissus plant is being reported for the first time from India.

5.
J Microbiol Biotechnol ; 27(9): 1724, 2017 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-28958134

RESUMEN

This erratum is being published to correct the error in the name of the strain in the paper by Siddikee et al. The name of the strain B. iodinum should be corrected as B. linens in title 'Isolation, Characterization, and Use for Plant Growth Promotion Under Salt Stress, of ACC Deaminase-Producing Halotolerant Bacteria Derived from Coastal Soil'.

6.
Clin Exp Dermatol ; 42(7): 728-734, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28649780

RESUMEN

BACKGROUND: Tranexamic acid (TXA) has been used orally, intravenously, topically and intradermally (microinjection, microneedling) for treating melasma. However, the comparative efficacy of these different routes of administration remains underevaluated. AIM: To ascertain the comparative efficacy of different routes of administration of TXA. METHODS: In total, 100 consecutive patients with melasma (8 men, 92 women, age range 18-55 years) were randomly assigned to one of two groups comprising 50 patients each. Group A (3 men, 47 women) received oral TXA 250 mg twice daily, while group B (5 men, 45 women) received intradermal microinjections of TXA 4 mg/mL every 4 weeks. The treatment continued for 12 weeks in both groups. Percentage reduction in baseline Melasma Area and Severity Index (MASI) was assessed at 4-week intervals, and response was scored as very good (> 75% reduction), good (50% to < 75% reduction), moderate (25% to < 50% reduction), mild (< 25% reduction) or no response. RESULTS: The study was completed by 39 patients in group A and 41 patients in group B. Very good response was seen in 25 and 32 patients in groups A and B, respectively, while good response was seen in 14 and 9 patients, respectively. Both treatment methods were equally effective, with an average reduction of MASI at 12 weeks of 77.96 ± 9.39 in group A and 79.00 ± 9.64 in group B. The main adverse effects were mild epigastric discomfort, hypomenorrhea, headache and injection site pain, which did not warrant discontinuation of treatment. Two patients in group A had relapses at 24 weeks. CONCLUSION: TXA appears to be an effective and safe treatment for melasma, irrespective of its route of administration.


Asunto(s)
Melanosis/tratamiento farmacológico , Ácido Tranexámico/administración & dosificación , Administración Oral , Adolescente , Adulto , Femenino , Humanos , Inyecciones Intradérmicas/efectos adversos , Masculino , Microinyecciones , Persona de Mediana Edad , Ácido Tranexámico/efectos adversos , Adulto Joven
7.
Cytokine ; 90: 124-129, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27865204

RESUMEN

BACKGROUND: Transforming growth factor ß (TGF-ß) is an anti-inflammatory cytokine and its role in hydrocephalus and stoke has been suggested. Tuberculous meningitis (TBM) is associated with exudates, stroke, hydrocephalus and tuberculoma, but the role of TGF-ß has not been evaluated in relation to these changes. AIM: To evaluate the cerebrospinal fluid (CSF) TGF-ß level in the patients with TBM, and correlate these with clinical findings, MRI changes, paradoxical response and outcome at 6months. METHODS: TBM patients diagnosed on the basis of clinical, CSF and MRI criteria were prospectively included. The clinical details including duration of illness, seizures, focal motor deficit, Glasgow Coma Scale (GCS) score and stage of TBM were noted. Presence of exudate, hydrocephalus, tuberculoma and infarction in MRI was also noted. MRI was repeated at 3months and presence of paradoxical response was noted. Cerebrospinal fluid TGF-ß was measured using ELISA on admission and repeated at 3months and these were compared with 20 controls. RESULTS: TGF-ß level was significantly higher in TBM compared to the controls (385.76±249.98Vs 177.85±29.03pg/ml, P<0.0001). TGF-ß correlated with motor deficit, infarction and tuberculoma on admission but did not correlate with CSF abnormalities, drug induced hepatitis, paradoxical response and outcome. TGF-ß level at 3months was significantly lower than the baseline but remained higher than the controls. CONCLUSION: CSF TGF-ß levels are elevated in TBM and correlate with infarction and tuberculoma.


Asunto(s)
Infarto Encefálico/líquido cefalorraquídeo , Factor de Crecimiento Transformador beta/líquido cefalorraquídeo , Tuberculoma Intracraneal/líquido cefalorraquídeo , Tuberculosis Meníngea/líquido cefalorraquídeo , Adolescente , Adulto , Anciano , Infarto Encefálico/diagnóstico por imagen , Infarto Encefálico/etiología , Infarto Encefálico/terapia , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tuberculoma Intracraneal/diagnóstico por imagen , Tuberculoma Intracraneal/terapia , Tuberculosis Meníngea/complicaciones , Tuberculosis Meníngea/diagnóstico por imagen , Tuberculosis Meníngea/terapia
8.
Allergol Immunopathol (Madr) ; 44(3): 246-56, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27046748

RESUMEN

BACKGROUND: Antigen exposure and persistent inflammation leads to structural changes in the asthmatic airways which are collectively termed as "airway remodelling". Presently available asthma medications ameliorate inflammations but are unable to prevent or reverse the airway remodelling process as most of the treatment strategies are only focused on inflammation instead of remodelling. METHODS: Curcumin, a phytochemical present in the rhizome of Curcuma longa is well known for its anti-inflammatory activity; however, the main drawback is its poor bioavailability which limits its therapeutic approval. So, the effect of nasal curcumin on acute and chronic asthma has been studied where short exposure to ovalbumin (4 days) represents acute phase whereas repeated exposures for longer (twice per week till 5 weeks) represents chronic asthma. Disodium cromoglycate (DSCG, 50mg/kg, i.p.) and dexamethasone (1mg/kg, i.p.) were used as standard drugs in acute and chronic model of asthma respectively. RESULTS: OVA-induced airway inflammation initiated in acute stage led to remodelling due to persistent inflammation, epithelial and sub epithelial thickening (smooth muscle thickening), extracellular matrix (ECM) deposition, goblet cell hyperplasia and mucus plug formation. Intranasal curcumin is effective in inhibiting airway inflammation and remodelling both by maintaining the structural integrity of lungs in terms of inflammation, airway wall thickening and mucus production. CONCLUSION: Our findings suggest that curcumin administered through nasal route might prove therapeutically efficient in inhibiting allergic airway inflammations and maintaining structural integrity in the mouse model of allergic asthma. This may lead to the development of curcumin aerosol in near future.


Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias)/efectos de los fármacos , Antiasmáticos/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Asma/tratamiento farmacológico , Curcumina/uso terapéutico , Inflamación/inmunología , Administración Intranasal , Remodelación de las Vías Aéreas (Respiratorias)/inmunología , Animales , Antiasmáticos/administración & dosificación , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/farmacocinética , Asma/inmunología , Disponibilidad Biológica , Enfermedad Crónica , Cromolin Sódico/administración & dosificación , Cromolin Sódico/uso terapéutico , Curcuma/química , Curcumina/administración & dosificación , Curcumina/farmacocinética , Dexametasona/administración & dosificación , Dexametasona/uso terapéutico , Modelos Animales de Enfermedad , Glucocorticoides/administración & dosificación , Glucocorticoides/uso terapéutico , Células Caliciformes/efectos de los fármacos , Células Caliciformes/inmunología , Humanos , Inflamación/tratamiento farmacológico , Ratones , Ratones Endogámicos BALB C , Ovalbúmina/inmunología
9.
Eur J Clin Microbiol Infect Dis ; 35(2): 305-10, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26718940

RESUMEN

Vascular endothelial growth factor (VEGF) and its receptors have been reported as severity markers of septicemia. Scrub typhus (ST) results in multi-organ dysfunction but the role of VEGF has not been evaluated. We report VEGF and its receptors in ST and its correlation with severity, outcome and laboratory findings. Thirty patients with ST diagnosed by solid phase immune chromatographic assay and Weil-Felix tests were included. Their clinical details, Glasgow Coma Scale (GCS), SOFA and modified Rankin Scale (mRS) scores and laboratory findings were noted. VEGF, VEGFR1 and VEGFR2 were done by ELISA at admission and repeated at 1 month. Outcome was defined at 1 month. Serum VEGF and VEGF-R1 levels were significantly higher and VEGFR2 was significantly lower in the ST patients compared to the controls. These levels significantly improved at 1 month. VEGF level correlated with SOFA score (p = 0.05) and SGPT (p = 0.04). VEGFR1 correlated with hemoglobin (p = 0.04), platelet count (p = 0.03), serum CK (p = 0.001), weakness (p = 0.04) and mRS score (p = 0.04). VEGFR2 did not correlate with any clinical or laboratory parameters. All the patients recovered with doxycycline. Serum VEGF and VEGFR1 levels increased in ST and suggest disease severity but do not predict outcome.


Asunto(s)
Tifus por Ácaros/diagnóstico , Factor A de Crecimiento Endotelial Vascular/sangre , Receptor 1 de Factores de Crecimiento Endotelial Vascular/sangre , Receptor 2 de Factores de Crecimiento Endotelial Vascular/sangre , Adolescente , Adulto , Anciano , Alanina Transaminasa/sangre , Antibacterianos/uso terapéutico , Biomarcadores/sangre , Niño , Preescolar , Doxiciclina/uso terapéutico , Ensayo de Inmunoadsorción Enzimática , Femenino , Escala de Coma de Glasgow , Humanos , Masculino , Persona de Mediana Edad , Orientia tsutsugamushi , Recuento de Plaquetas , Tifus por Ácaros/tratamiento farmacológico , Tifus por Ácaros/microbiología , Resultado del Tratamiento , Adulto Joven
10.
Indian J Lepr ; 88(1): 13-19, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29741821

RESUMEN

The rheumatological manifestations of leprosy occur singly or in varying combinations, particularly during lepra reactions. Despite being third most common, these remain under diagnosed and under reported. This study has been carried out to study the spectrum of rheumatological manifestations in leprosy patients. One hundred consecutive patients of leprosy presenting during January to December 2013 were studied for rheumatological manifestations. Complete hemogram, serum biochemistry, urinalysis, rheumatoid factor, ASO titer, C-reactive protein, ANA, and x-rays for hands, feet, chest and involved joints were performed. These 100 (M:F 66:34) patients aged between 16-80 years had indeterminate (2 patients), TT (4 patients), BT (26 patients), BB (2 patients), and LL leprosy (32 patients). 27 patients had rheumatological manifestations; arthritis involving large or small joints in 23 patients being the commonest. 7 of 24 patients in type-1 lepra reaction had enthesitis in 3 patients and oligoarthritis in 4 patients. Rheumatoid arthritis-like polyarthritis was noted in 19 patients with type-2 reaction. Tenosynovitis, dactylitis, bony changes were also noted. Except for one case, these features were present in patients having lepra reactions. Rheumatoid factor in 14, ANA in 15, C-reactive protein in 45 cases was positive. ASO was positive 34 cases. Symmetrical polyarthritis involving small joints of hands and feet, oligoarthritis, enthesitis and dactylitis are common in leprosy particularly with borderline leprosy, type-2 lepra reaction especially in the presence of positive RAfactor.


Asunto(s)
Lepra/complicaciones , Enfermedades Reumáticas/etiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Proteína C-Reactiva/metabolismo , Femenino , Humanos , India , Lepra/sangre , Masculino , Persona de Mediana Edad , Enfermedades Reumáticas/sangre , Factor Reumatoide/sangre , Reumatología , Centros de Atención Terciaria , Adulto Joven
11.
J Med Virol ; 87(9): 1449-55, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25970161

RESUMEN

Vascular permeability determines the severity of dengue virus infection. Vascular endothelial growth factor (VEGF) and its (receptor 1) R1 and (receptor 2) R2 receptors may provide insight about the neurological complications of dengue. We report VEGF and its R1 and R2 receptors level in dengue patients and correlate these with neurological complications. Consecutive patients with dengue were subjected to clinical and neurological evaluations. Their blood counts, serum chemistry, including liver and kidney function tests, serum creatine kinase (CK), and albumin were measured. VEGF, VEGFR1 and VEGFR2 were measured by ELISA in the patients and 16 matched controls. Twenty four patients with dengue were included whose ages ranged between 15 and 67 years, and nine of whom were females. Serum VEGF level was insignificantly lower in dengue patients whereas VEGFR1 was significantly higher (P = 0.01) and VEGFR2 was significantly lower (P = 0.005) compared to controls. VEGFR2 correlated with systolic blood pressure, coagulopathy, and serum CK levels. None of the other clinical and biochemical parameters correlated with VEGF and VEGFR1 levels. VEGFR1 and R2 normalized at 1 month. VEGFR2 correlates with the clinical severity of dengue and muscle dysfunction.


Asunto(s)
Dengue/sangre , Factor A de Crecimiento Endotelial Vascular/sangre , Receptor 1 de Factores de Crecimiento Endotelial Vascular/sangre , Receptor 2 de Factores de Crecimiento Endotelial Vascular/sangre , Adolescente , Adulto , Anciano , Dengue/complicaciones , Dengue/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Musculares/etiología , Enfermedades Musculares/virología , Receptor 1 de Factores de Crecimiento Endotelial Vascular/química , Adulto Joven
12.
J Appl Microbiol ; 112(4): 793-808, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22324517

RESUMEN

AIMS: The aim of this study was to identify the gene responsible for degradation of toxic allelochemicals of Parthenium by generating Tn5-induced mutant of Pseudomonas putida NBRIC19. Furthermore, the study characterizes the mutant at physiological, biochemical and molecular level that helped in understanding the mechanisms of reducing the allelopathic inhibition of Parthenium by Ps. putida NBRIC19. METHODS AND RESULTS: Tn5 mutant S-74.3 showing inability to degrade toxic allelochemicals was selected after screening 22 000 transconjugants. Tn5 flanking SucB gene (dihydrolipoamide succinyltransferase) of Ps. putida NBRIC19 was found to be responsible for the degradation of toxic allelochemicals that also affected biofilm formation, chemotaxis and alginate production under toxic environment of allelochemicals. Phenotypic microarray data revealed that the respiratory activity of Ps. putida NBRIC19 and S-74.3 differed on 47 substrates including amino acids, carboxylic acids, peptides and some chemical inhibitors. CONCLUSIONS: Study revealed that SucB gene regulates processes either directly or indirectly in Ps. putida NBRIC19, which on inactivation made the mutant less compatible for tolerating stress. SIGNIFICANCE AND IMPACT OF THE STUDY: This work provides the first evidence for a functional role of Ps. putida SucB gene in degradation of toxic allelochemicals of Parthenium that lead to reversal of plant growth inhibition by these toxic allelochemicals. The investigation also revealed interesting features about the involvement of microbes in plant-plant allelopathic interactions.


Asunto(s)
Asteraceae/química , Feromonas/metabolismo , Pseudomonas putida/genética , Pseudomonas putida/metabolismo , Aciltransferasas/genética , Aciltransferasas/metabolismo , Alginatos/metabolismo , Ácido Glucurónico/metabolismo , Ácidos Hexurónicos/metabolismo , Pseudomonas putida/enzimología , Pseudomonas putida/crecimiento & desarrollo
13.
Antonie Van Leeuwenhoek ; 101(2): 453-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21909789

RESUMEN

Chromium (Cr), with its great economic importance in industrial use, is a major metal pollutant of the environment. It affects soil microbial activity and soil fertility, resulting in losses in yield of plants. Paenibacillus lentimorbus B-30488(r) (B-30488(r)) tolerated 200 µg ml(-1) of Cr under in vitro conditions and produced the plant growth promoting substance indole acetic acid in the presence of Cr. Our in vitro study indicates enhancement in B-30488(r) biofilm formation by sodium alginate (SA) and calcium chloride (CaCl(2)) both in absence and presence of supplemented Cr(VI) as compared to unsupplemented control. The plant growth promoting effects caused by the B-30488(r) biofilm in rhizosphere of chickpea under Cr(VI) stress suggests a phytoprotective role of B-30488(r) biofilm. Our study reflects the multifarious role of strain B-30488(r) and presents it as a potent plant growth promoting and bioremediation agent useful in Cr-contaminated rhizosphere soil, whereby the SA and CaCl(2) induced B-30488(r) biofilm on plant root acts as a shield in preventing the direct access of toxic Cr to plant tissues, thus reducing its uptake in plants.


Asunto(s)
Cromo/metabolismo , Cicer/crecimiento & desarrollo , Paenibacillus/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Biodegradación Ambiental , Cicer/metabolismo , Cicer/microbiología
14.
Clin Exp Dermatol ; 36(2): 169-73, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20545955

RESUMEN

There is a dearth of studies comparing the efficacy of psoralen ultraviolet A (PUVA) and narrowband (NB)-UVB in psoriasis in South Asian patients. Patients having plaque psoriasis with > 20% body surface area involvement were randomly assigned to one of two groups (group A: NB-UVB, group B: PUVA). The response to treatment was assessed by the Psoriasis Area and Severity Index (PASI) at baseline and every 2 weeks thereafter. The maximum possible treatment duration was 16 weeks. In total, 43 patients (21 NB-UVB, 22 PUVA) completed the study. Marked improvement was seen in 80.9% of the patients in group A and 81.8% in group B (NS: P > 0.05). The mean ± SD time taken to achieve marked improvement was 9.9 ± 3.3 and 9.9 ± 3.5 weeks, respectively. In total, 29 patients were available for the analysis of the remission data at 6 months after treatment completion; 26.7% of the patients in group A and 42.8% in group B were in remission (NS: P > 0.05). Both methods seem to be equally effective in achieving clearance and maintaining remission of severe chronic plaque psoriasis in patients with Fitzpatrick skin type 4 and 5.


Asunto(s)
Terapia PUVA/métodos , Psoriasis/tratamiento farmacológico , Psoriasis/radioterapia , Terapia Ultravioleta/métodos , Adulto , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Psoriasis/patología , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
15.
Lett Appl Microbiol ; 50(2): 205-10, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20002573

RESUMEN

AIMS: To isolate the rhizosphere competence-defective transposon Tn5 mutant of Pantoea agglomerans NBRISRM (SRM) and to identify the gene causing defect in its root colonization ability. METHODS AND RESULTS: From over 5000 clones containing Tn5, one mutant P. agglomerans NBRISRMT (SRMT) showing 6 log units less colonization when compared with SRM, after 30 days in sand-nonsterilized soil assay system was selected for further work to determine the effects of the mutation on rhizosphere competence. Southern hybridization analysis of restricted genomic DNA of SRMT demonstrated that the mutant had a single Tn5 insert. SRM increased in titre to about 2 x 10(8) CFU g(-1) root, compared with the indigenous bacterial population of heterotrophs of about 5 x 10(7) CFU g(-1) root. In contrast, 30 days later, the titre value of SRMT was almost undetectable at 1 x 10(2) CFU g(-1) root, demonstrating its inability to survive and colonize the rhizosphere. Sequencing of the flanking region of the Tn5 mutant revealed that Tn5 disrupted the purB gene. CONCLUSIONS: A defect in the colonization phenotype of the SRMT was attributed to the disruption in adenylosuccinate lyase (EC 4.3.2.2) which is encoded by the pur B gene and is required for rhizosphere colonization in P. agglomerans. Significantly less exopolysaccharide and biofilm was formed by SRMT when compared to SRM, because of the disruption of the purB gene. SIGNIFICANCE AND IMPACT OF THE STUDY: This work provides the first evidence for a functional role of purB gene in rhizosphere competence and root colonization by any rhizobacteria.


Asunto(s)
Adenilosuccinato Liasa/metabolismo , Proteínas Bacterianas/metabolismo , Genes Bacterianos/fisiología , Pantoea/enzimología , Rizoma/microbiología , Adenilosuccinato Liasa/genética , Proteínas Bacterianas/genética , Biopelículas/crecimiento & desarrollo , Elementos Transponibles de ADN , Mutagénesis Insercional , Mutación , Pantoea/genética , Polisacáridos Bacterianos/biosíntesis , Polisacáridos Bacterianos/genética , Rizoma/enzimología , Rizoma/genética , Microbiología del Suelo
16.
Hum Biol ; 76(5): 743-63, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15757245

RESUMEN

We attempt to address the issue of genetic variation and the pattern of male gene flow among and between five Indian population groups of two different geographic and linguistic affiliations using Y-chromosome markers. We studied 221 males at three Y-chromosome biallelic loci and 184 males for the five Y-chromosome STRs. We observed 111 Y-chromosome STR haplotypes. An analysis of molecular variance (AMOVA) based on Y-chromosome STRs showed that the variation observed between the population groups belonging to two major regions (western and southwestern India) was 0.17%, which was significantly lower than the level of genetic variance among the five populations (0.59%) considered as a single group. Combined haplotype analysis of the five STRs and the biallelic locus 92R7 revealed minimal sharing of haplotypes among these five ethnic groups, irrespective of the similar origin of the linguistic and geographic affiliations; this minimal sharing indicates restricted male gene flow. As a consequence, most of the haplotypes were population specific. Network analysis showed that the haplotypes, which were shared between the populations, seem to have originated from different mutational pathways at different loci. Biallelic markers showed that all five ethnic groups have a similar ancestral origin despite their geographic and linguistic diversity.


Asunto(s)
Cromosomas Humanos Y/genética , Etnicidad/genética , Frecuencia de los Genes , Variación Genética , Genética de Población , Haplotipos , Secuencias Repetidas en Tándem , Marcadores Genéticos , Humanos , India , Masculino
17.
Ann Hum Biol ; 29(5): 513-25, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12396371

RESUMEN

OBJECTIVE: The present investigation reports the genetic variation observed at two tetrameric short tandem repeat (STR) loci on chromosome 12 (D12S66 and D12S67) among five anthropologically distinct population groups of India. SUBJECTS AND METHODS: A total of 277 random, normal and healthy volunteers were investigated for the D12S66 locus, and 236 for the locus D12S67, from five ethnic groups of India. Two of these belong to the state of Maharashtra in western India (Konkanastha Brahmins and Marathas) and three from the state of Kerala in South India (Nairs, Ezhavas and Muslims). DNA was extracted from peripheral blood samples, amplified by duplex polymerase chain reaction (PCR) and electrophoresed on 6% denaturing urea (7 M) gel electrophoresis. The analysis was performed on ALF Express DNA sequencer (Amersham Pharmacia Biotech) using Fragment Manager software. Statistical analysis was done by using Arlequin ver. 1.1. RESULTS: At D12S66 locus, a total of nine alleles (8-17 repeats) and 27 genotypes were detected with an observed heterozygosity ranging from 0.55 to 0.91. At the D12S67 locus, nine alleles (36-44 repeats) and 33 genotypes were observed with a heterozygosity ranging from 0.74 to 0.89. Both the loci displayed high Power of Discrimination (PD) which ranged from 0.81 to 0.91 and Polymorphic Information Content (PIC) ranging from 0.68 to 0.84. At D12S66, two alleles were detected for the first time in these population groups which were not reported earlier. The level of gene differentiation (G(ST) value, 0.02) was moderate at these two loci, indicating a close relationship among the population groups. CONCLUSIONS: From this investigation, it is concluded that both the tetrameric loci are highly polymorphic and informative, and can be used for the characterization of the Indian population groups in addition to other well-studied STR loci.


Asunto(s)
Cromosomas Humanos Par 12/genética , Repeticiones de Microsatélite , Alelos , Etnicidad/genética , Frecuencia de los Genes , Variación Genética , Genética de Población , Genotipo , Heterocigoto , Humanos , India
18.
Hum Biol ; 74(3): 345-61, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12180760

RESUMEN

The present study reports the genetic variation observed among five anthropologically distinct population groups of India, using four highly polymorphic minisatellite loci (D1S80, D17S5, D19S20, and APOB 3' VNTR) in order to examine the effect of geographical and linguistic affiliations on the genetic affinities among these groups. Random individuals from five ethnic groups were studied; the sample size ranged from 235 to 364. The population groups belong to two geographically separated regions of India, the state of Maharashtra (western India) and the state of Kerala (southern India). The two Maharashtrian groups (Konkanastha Brahmins and Marathas) speak "Marathi," an Indo-European language, whereas the three Kerala population groups (Nairs, Ezhavas, and Muslims) speak "Malayalam," an Indo-Dravidian language. Genomic DNA was extracted from peripheral blood samples and analyzed using amplified fragment length polymorphism (Amp-FLP) technique. All four loci displayed high heterozygosity with average heterozygosity in the range of 0.82 to 0.84. The Polymorphic Information Content and Power of Discrimination were > or = 0.75 and > or = 0.80, respectively. The coefficient of gene differentiation was found to be low (average G(ST) = 1.2%; range between 0.6% at D1S80 locus to 1.6% at APOB 3' VNTR locus) across the loci, indicating close affinity among the population groups. The neighbor-joining tree revealed two clear clusters, one for the two Maharashtrian population groups and the other for the three Kerala population groups. The results obtained are in conformity with the geographical and linguistic backgrounds of the studied populations.


Asunto(s)
Etnicidad/genética , Genética de Población , Repeticiones de Minisatélite/genética , Polimorfismo Genético , Alelos , Femenino , Frecuencia de los Genes , Variación Genética , Genotipo , Heterocigoto , Humanos , India , Masculino , Polimorfismo de Longitud del Fragmento de Restricción
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