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1.
ISA Trans ; 147: 215-226, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38402102

RESUMEN

A hybrid technique is proposed in this manuscript for the optimal design of an induction motor (IM) drive for the dynamic load profiles during torque and flux control. The proposed hybrid method combines a Ladder-Spherical-Evolution-Search-Algorithm (LSE) and a recalling-enhanced recurrent-neural network (RERNN), which is called an LSE-RERNN technique. The major objective of the proposed method is to minimize IM losses while maintaining control over speed and torque. The proposed method effectively tunes the gain parameter of the PI controller for flux and torque regulation. The LSE methodgenerates a set of gain parameters optimally predicted by RERNN. The method reduces losses without prior knowledge of load profiles, achieving energy savings for steady-state optimum flux. The performance of the proposed technique is done in the MATLAB and is compared with different existing techniques. The value of the proposed method for the mean is 0.328, the standard deviation (SD) is 0.00334, and the median is 0.4173. The loss of the proposed method is much less than 0.3 W while compared to different existing approaches. Moreover, the computation time of the proposed approach is lesser than the existing techniques.

2.
Sci Rep ; 13(1): 21415, 2023 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-38049427

RESUMEN

Ornamental fish keeping is the second most preferred hobby in the world and it provides a great opportunity for entrepreneurship development and income generation. Controlling the environment in ornamental fish farm is a considerable challenge because it is affected by a variety of parameters like water temperature, dissolved oxygen, pH, and disease occurrences. One particular interesting ornamental fish species is goldfish (Carassius auratus). Machine learning (ML) and deep learning technique have significant potential in analysing voluminous data collected from fish farm. Through this technique, the fish farmers can get insight on feeding behaviour, fish growth patterns, predict diseases/stress, and environmental factors affecting fish health. The aim of the study is to analyze the behavioural changes in goldfish due to alterations in environmental parameters (water temperature and dissolved oxygen). Decision tree, Naïve Bayes classifier, K-nearest neighbour (KNN), and linear discriminant analysis (LDA) were used to analyse the behavioural change data. To compare the performance between all four classifiers, cross validation and confusion matrix used. The cross-validation error of LDA, Naïve Bayes classification, KNN and decision tree was 19.86, 28.08, 30.14 and 13.78 respectively. Decision tree was proved to be the most accurate and effective classifier. Different temperature and DO range were taken to predict fish behaviour. Some findings are, the behaviour of fish was rest between temperature 37.85 °C and 40.535 °C, erratic when temperature was greater than or equal to 40.535 °C, gasping when temperature was between 37.85 and 40.535 °C and when DO concentration was less than 6.58 mg/L. Blood parameter analysis has been done to validate the change in external behaviours with change in physiological parameters.


Asunto(s)
Carpa Dorada , Oxígeno , Animales , Teorema de Bayes , Carpa Dorada/fisiología , Temperatura , Agua
3.
Nanotheranostics ; 7(4): 412-423, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37650012

RESUMEN

Antimicrobial polymers (AMP) appear to be a promising candidate to deal with the current scenario of bacterial resistance against conventional drugs and antibiotics as they mainly depend on disrupting the bacterial membrane. This work investigates the effect of polycations bearing aromatic and aliphatic pendant cationic groups on the antimicrobial performance of AMP. A radical polymerization strategy was adopted to synthesize two different copolymers and convert them into polycations upon post-modification. Polyelectrolytes were converted into nanoparticles by nanoprecipitation and named PE1 and PE2. Polymers were analyzed by NMR, FT-IR, and gel permeation chromatography (GPC). PE1 and PE2 nanoparticles were uniform, spherical particles from FESEM, size, and zeta potential measurements. The antimicrobial properties of polyelectrolytes were determined against pathogenic Escherichia coli (E. coli), Bacillus Subtilis (B. Subtilis), Bacillus Amyloliquefaciens (B. Amyloliquefaciens) and Citrobecter Freundii (C. Freundii) bacterias. The biocidal activity determination studies showed that polyelectrolyte PE2 with aromatic pendant units outperformed PE1 with the aliphatic pendant group. This work highlights the remarkable effect of aromatic segmentation, which provides microbial inhibition, and killing is demonstrated as an antibacterial surface coating.


Asunto(s)
Escherichia coli , Nanopartículas , Polielectrolitos , Espectroscopía Infrarroja por Transformada de Fourier , Polímeros , Antibacterianos/farmacología
4.
Vet Parasitol Reg Stud Reports ; 26: 100628, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34879939

RESUMEN

Bovine tropical theileriosis (BTT) is a tick-borne protozoan disease of cattle and responsible for major economic losses to the dairy farmers in India. This report describes diagnosis, genotyping and successful treatment of heavy infection of Theileria annulata in an organized dairy farm at Kattupakkam, Chennai. Four cross bred cows of 2 to 5 years of age showed clinical signs i.e., anorexia, salivation and panting. Clinical examination revealed pyrexia (40.0 °C to 40.1 °C), pale mucus membranes, enlarged prescapular lymph nodes and haemoglobinuria. The peripheral blood smear examination of infected cows revealed presence of piroplasm within the RBCs indicating high parasitemia. Haematology results suggested that decreased levels of Hb, RBC, WBC and PCV in the infected cows when compared with normal reference values. There were increased serum ALT and AST values and reduced serum total protein, albumin, calcium and phosphorous values in the infected cows. Semi-nested PCR using T. annulata specific oligonucleotide primers amplified 199 bp of the partial T. annulata 18S rRNA gene. Presence of four satellite markers TS6, TS8, TS9, and TS12 in the Theileria annulata isolates 1 and 2 indicating that the isolates were the same haplotype and suggested the infection in the farm was due to a single haplotype of T. annulata parasite. Based on the clinical signs, microscopic examination of blood smear and molecular diagnosis, the condition was diagnosed as tropical theileriosis. Infected cows were successfully treated with a single deep intramuscular injection of buparvaquone (Zubion®, INTAS pharmaceuticals LTD, Ahmedabad, India) along with supportive medication.


Asunto(s)
Theileria annulata , Theileriosis , Drogas Veterinarias , Animales , Bovinos , Femenino , Genotipo , India , Theileria annulata/genética , Theileriosis/tratamiento farmacológico
5.
Math Biosci Eng ; 18(3): 2384-2400, 2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33892551

RESUMEN

In this work, we study the problem of p-th moment global exponential stability for functional differential equations and scalar chaotic delayed equations under random impulsive effects. Meanwhile, the p-th moment global exponential synchronization for the proposed equations is also discussed, whereas the main results are proved by using Lyapunov function and Razumikhin technique. Furthermore, the impact of fixed and random time impulses are presented by applying the results to Mackey Glass blood cell production model and Ikeda bistable resonator model. Finally, the effectiveness of fixed and random impulses are depicted via graphical representations.

6.
Acta Virol ; 62(1): 86-97, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29521107

RESUMEN

Infectious bursal disease virus isolates obtained from southern parts of India were subjected to comparative sequencing and phylogenetic analysis of 743bp hypervariable region of VP2. The sequence analysis showed that among eight isolates, only HY12 showed the characteristic conserved amino acid residues at 256I, 294I, and 299S of vvIBDV. Six isolates BGE14, PY12, NKL14, VCN14, RPM14 and EDE14 had conserved amino acid residues at 256I and 299S, whereas at residue 294, isoleucine was substituted by valine. The remaining isolate MB11 had leucine at residue 294 and asparagine at residue 299 similar to classical strain 52/70. The serine-rich heptapeptide sequence SWSASGS adjacent to the second hydrophilic region was conserved in all seven Indian IBDV isolates except isolate MB11. Conservation of this sequence was earlier reported to be an indication of a virus isolate being pathogenic in nature. The reported heptapeptide sequence of the classical strain is 'SWSARGS'. In the present study, 'SWSARGS' heptapeptide sequence was observed in MB11 isolate. The pathogenicity trials conducted with these isolates further confirmed the genome analysis in classification. This study further reveals that the circulating IBDV strains in India could be diverse in nature.


Asunto(s)
Infecciones por Birnaviridae/veterinaria , Pollos , Virus de la Enfermedad Infecciosa de la Bolsa/genética , Enfermedades de las Aves de Corral/virología , Proteínas Estructurales Virales/genética , Animales , Infecciones por Birnaviridae/epidemiología , Infecciones por Birnaviridae/virología , India/epidemiología , Filogenia , Enfermedades de las Aves de Corral/epidemiología , Proteínas Estructurales Virales/química
7.
Anesth Essays Res ; 11(3): 627-629, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28928560

RESUMEN

BACKGROUND: Spinal anesthesia is a safe alternative to general anesthesia and often the anesthetic technique of choice in many lower abdominal and lower limb surgeries in children. As the vertebral column and spinal cord grows variedly with age and not weight, we planned to administer an age-based dosing schedule of hyperbaric bupivacaine in the intra-thecal space in select infra umbilical surgeries in children. The aim was to find out the efficacy and complications associated with this dosage. METHODOLOGY: Twenty-five pediatric patients between 2 and 12 years, posted for elective infra umbilical surgeries were given a sedation as a combination of effective doses of pentazocine, midazolam, and atropine. In all those patients, spinal anesthesia was administered at a dose of age/5 of hyperbaric bupivacaine. The number of attempts, the onset of blockade, the mean sensory level, and the duration of anesthesia were noted. Any other complications were also noted. RESULTS: The mean and standard deviation of age is 7.68 ± 2.49 years. Intra-thecal anesthesia was administered successfully in the first attempt in 88% of cases whereas the remaining needed the second attempt. Three patients needed intravenous ketamine of 0.25 mg/kg additionally for preoperative sedation. The sensory level was between T6 and T10 with a mean of T8.5. There were no intra-operative complications. In all patients, surgery was finished within the duration of anesthesia of approximately 60 min. There was no conversion to general anesthesia in any case, but a three patients required dose of 0.25 mg/kg of intravenous ketamine as a calming dose. CONCLUSION: Administration of age-based local anesthetic dosing of hyperbaric bupivacaine in the intra-thecal space by utilizing a new formula of age/5 (Partha formula) is successful in a pilot study in Indian children for infra-umbilical surgeries. There were no observed complications.

8.
J Parasit Dis ; 40(3): 1038-43, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27605834

RESUMEN

Toxocara canis is a widespread gastrointestinal nematode parasite of dogs and cause Toxocara larva migrans, an important zoonotic disease in humans on ingestion of infective eggs. Toxocarosis is one of the few human parasitic diseases whose serodiagnosis uses a standardized antigen, T. canis excretory secretory antigen (TES). The present study describes collection of T. canis adult worm, collection and embryonation of T. canis eggs, hatching and separation of T. canis larvae, in vitro maintenance of T. canis second stage larvae for production of TES, concentration of culture fluid TES and yield of TES in correlation with various methods cited in literature.

9.
Genome Announc ; 4(4)2016 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-27445389

RESUMEN

The novel infectious bursal disease virus (IBDV) isolate BGE14/ABT1/MVC/India is a very virulent IBDV that was isolated from broiler flocks in southern parts of India during 2014. Here, we report, for the first time in India, the complete genome sequence of BGE14/ABT1/MVC/India, a reassortment strain with segments A and B derived from a very virulent IBDV strain and an attenuated IBDV, respectively. The findings from this study provide additional insight into the genetic exchange between attenuated and very virulent strains of IBDV circulating in the field.

10.
Genome Announc ; 4(3)2016 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-27174268

RESUMEN

Infectious bursal disease virus is an avian pathogen that causes huge morbidity and mortality in the poultry sector all over the world. Here, we report the full-length genome sequence of an Indian strain, MB11/ABT/MVC/2016, isolated from a commercial broiler flock. This is a first report of a complete genome sequence of infectious bursal disease virus from India.

11.
Acta Virol ; 60(1): 34-40, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26982465

RESUMEN

The reverse transcription PCR (RT-PCR) combined with restriction fragment length polymorphism (RFLP) is used for the differentiation of classical virulent (cv), virulent (v) and very virulent (vv) strains of infectious bursal disease virus (IBDV) isolates from chicken bursal tissues in southern states of India. In the present study, six different isolates (MB11, HY12, PY12, BGE14, VCN14 and NKL14) of IBDV strains were subjected for genotyping along with vaccine virus (Georgia, intermediate strain) using RT-PCR for amplification of a 743 bp sequence in the hypervariable region of VP2 gene followed by restriction enzyme digestion with 5 different restriction enzymes (BspMI, SacI, HhaI, StuI and SspI). The RT-PCR products obtained from vvIBDV strains were digested by SspI enzyme except PY12, BGE14 and MB11 isolates. The SacI digested the isolate MB11, PY12 and the vaccine strain, but it did not cleave the very virulent isolates of IBDV. HhaI cleaved all the isolates with different restriction profile patterns. StuI digested all the vvIBDV isolates and BspMI was not able to differentiate field isolates from vaccine strain. Though RT-PCR combined with RFLP is a genotypic method, further confirmation of serotypes to distinguish the vvIBDV from cvIBDV has to be carried out using pathogenicity studies.


Asunto(s)
Análisis del Polimorfismo de Longitud de Fragmentos Amplificados/métodos , Infecciones por Birnaviridae/veterinaria , Virus de la Enfermedad Infecciosa de la Bolsa/aislamiento & purificación , Enfermedades de las Aves de Corral/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Animales , Infecciones por Birnaviridae/epidemiología , Infecciones por Birnaviridae/virología , Pollos , Genotipo , India/epidemiología , Virus de la Enfermedad Infecciosa de la Bolsa/clasificación , Virus de la Enfermedad Infecciosa de la Bolsa/genética , Polimorfismo de Longitud del Fragmento de Restricción , Enfermedades de las Aves de Corral/epidemiología
12.
J Mater Chem B ; 4(2): 299-308, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-32263372

RESUMEN

Intracellular detection and imaging of labile iron(ii) pools is very important in tracking physiological processes that demand new and rapid sensing probes. In this report, we present a water soluble polymer based probe for the fluorescence sensing and live cell imaging of labile Fe2+ ions with high selectivity for the first time. The polymer probe was based on conjugated polyfluorene which was appended with amino acid (l-glutamic acid). The biocompatibility of the polymer was confirmed from an MTT assay which demonstrated >90% cell viability even at 300 µg ml-1 loading of polymers. Simple glutamic acid did not show selectivity towards any of the divalent ions. However, glutamic acid appended polyfluorene exhibited selective chelation to Fe2+ ions resulting in immediate sensing activity for Fe2+ ions in water and living cells with fluorescence turn-off response. The limit of detection of the PF-Ph-GA polymer probe was 46 (±2) nM which indicated high sensitivity for Fe2+ over other ions reported in the literature. The polymer also exhibited improved sensing activity in the range of intracellular pH (5-9) which is advantageous in differentiating endogenous changes. The probe was successfully applied for the fluorescence imaging of intracellular and supplemented labile iron(ii) pools in living HeLa cells.

13.
Chem Commun (Camb) ; 51(43): 8931-4, 2015 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-25924985

RESUMEN

We present a polyfluorene appended with protected l-glutamic acid that exhibited a reversible α-helix/ß-sheet-like conformation and helical porous fibrous morphology mimicking the super-structure of proteins. The new homochiral polymer probe enabled efficient heterogeneous enantioselective separation and chiral sensing of a wide variety of substrates from their aqueous racemic mixture using an easy 'Filter-and-Separate' method.


Asunto(s)
Materiales Biomiméticos/química , Polímeros/química , Cromatografía Líquida de Alta Presión , Dicroismo Circular , Filtración , Ácido Glutámico , Microscopía Electrónica de Rastreo , Polímeros/aislamiento & purificación , Porosidad , Estereoisomerismo
14.
J Parasit Dis ; 38(4): 429-31, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25320498

RESUMEN

Fresh dung samples from cattle nearby and tribal areas of free-ranging regions, Mudumalai Tiger Reserve, Anamalai Tiger Reserve and forest divisions of Sathyamangalam-Erode of Tamil Nadu state were examined for identification of endoparasitic infection. A total of 50 dung samples were collected and examination of samples revealed the presence of eggs of Strongyle, Strongyloides sp., amphistomes, Toxocara sp. and oocysts of Eimeria sp. The risk of parasitic disease transmission from domestic livestock to wild populations was discussed.

15.
Appl Biochem Biotechnol ; 172(7): 3635-45, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24562978

RESUMEN

The conventional avian influenza vaccines rely on development of neutralizing antibodies against the HA and NA antigens. However, these antigens are highly variable, and hence there is a need for better vaccine candidates which would offer broader protection in animals. The M1 of avian influenza is another major structural protein that has conserved epitopes that are reported to induce CD8+ T cells and can contribute to protection against morbidity and mortality from influenza. Hence in an effort to study the immune response of rM1 either alone or in combination with rHA, the hemagglutinin (HA) and matrix protein (M1) of A/Hatay/2004/H5N1 strain of avian influenza were expressed in Pichia pastoris as his-tagged proteins and purified through Ni-NTA chromatography. The His-tag was removed using TEV protease cleavage site and the immunogenicity of purified rHA and rM1 either alone or in combination was determined in mice. One group of mice was immunized with 5 µg of purified rHA, the other group was immunized with rM1, and a third group of mice were immunized with 5 µg of rHA and rM1. All the animals were boosted twice, once on 28 days postimmunization (dpi) and the second on 42 dpi. The immune response was evaluated by enzyme-linked immunosorbent assay (ELISA) and hemagglutination inhibition (HI) assay. The group of mice immunized with rHA and rM1 together showed significantly higher immune response against rHA and rM1 than mice immunized with either HA or M1 antigens. The addition of rM1 with rHA resulted in increased HI titer in animals immunized with both the antigens. These results suggest that the HA and M1 expressed in P. pastoris can be utilized in combination for the development of faster and cost-effective vaccines for circulating and newer strains of avian influenza and would aid in combating the disease in a pandemic situation, in which production time matters greatly.


Asunto(s)
Hemaglutininas Virales/inmunología , Subtipo H5N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunología , Proteínas de la Matriz Viral/inmunología , Animales , Anticuerpos Antivirales/inmunología , Femenino , Hemaglutininas Virales/administración & dosificación , Hemaglutininas Virales/genética , Humanos , Subtipo H5N1 del Virus de la Influenza A/genética , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la Influenza/genética , Gripe Humana/prevención & control , Gripe Humana/virología , Ratones , Pichia/genética , Pichia/metabolismo , Proteínas de la Matriz Viral/administración & dosificación , Proteínas de la Matriz Viral/genética
16.
Appl Biochem Biotechnol ; 169(2): 431-7, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23212848

RESUMEN

Microscopic agglutination test (MAT) is the standard method for the diagnosis of leptospirosis, which is laborious and the interpretation of the results is subjective. The present work describes the use of recombinant-based IgG ELISA for the serodiagnosis of leptospirosis. We used recombinant outer membrane protein OmpL1 as an antigen for conducting IgG enzyme-linked immunosorbent assay (ELISA). A total of 475 canine serum samples were subjected to IgG ELISA; 294 sera were positive to ELISA, while 283 were positive to MAT. All samples that were positive to MAT were positive to ELISA also, however, few samples which were negative to MAT were positive to ELISA, which suggested that recombinant-based IgG ELISA showed 100 % sensitivity when compared to MAT. Thus, this present study showed that recombinant OmpL1-based IgG ELISA appears to be a better alternative to MAT for the diagnosis of leptospirosis and rOmpL1 protein could be used as a potential diagnostic antigen in different assay formats for leptospirosis.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/inmunología , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Leptospirosis/diagnóstico , Leptospirosis/veterinaria , Animales , Perros , Leptospirosis/inmunología , Proteínas Recombinantes/inmunología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
Comp Immunol Microbiol Infect Dis ; 34(1): 17-22, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19906426

RESUMEN

An IgG-ELISA used recombinant antigen and a rapid flow-through enzyme immunoassay were developed for rapid screening of leptospiral antibodies in dogs using recombinant LipL41, which is one of the conserved outer membrane proteins in pathogenic leptospires as the coating antigen. Results from this study were compared with the standard microscopic agglutination test and found that the sensitivity and specificity of the enzyme-linked immunosorbent assay were 75.46% and 93.29% and whereas that of flow-through-based dot-immunobinding assay were 87.73% and 89.63%, respectively. Relative merits of these tests were also assessed. The flow-through-based dot-immunobinding assay was thus proved to be a valid screening test for canine leptospirosis.


Asunto(s)
Enfermedades de los Perros/diagnóstico , Inmunoensayo , Leptospirosis/veterinaria , Pruebas Serológicas/métodos , Pruebas de Aglutinación , Animales , Antígenos Bacterianos/metabolismo , Perros , Ensayo de Inmunoadsorción Enzimática/normas , Femenino , Inmunoensayo/normas , Leptospira/fisiología , Leptospirosis/diagnóstico , Masculino , Proteínas Recombinantes de Fusión/metabolismo , Sensibilidad y Especificidad
18.
Trop Anim Health Prod ; 42(2): 217-22, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19680775

RESUMEN

The efficacy of a recombinant leptospiral outer membrane protein LipL41 as an antigen for conducting IgG-Enzyme linked immunosorbent assay (ELISA) and latex agglutination test (LAT) for serodiagnosis of bovine leptospirosis was evaluated. The recombinant LipL41 antigen developed and used for detecting the antibodies was specific in detection of the pathogenic serovars of Leptospira, as the expression of the LipL41 antigen is restricted only to pathogenic leptospires. A total of 430 bovine serum samples were subjected to IgG-ELISA and LAT, and the sensitivity and specificity were assessed in comparison with microscopic agglutination test (MAT). The sensitivity and specificity of IgG-ELISA and LAT were 86.84% and 93.16%, and 95.42% and 98.33% respectively. Both the tests are found to be sensitive, specific and concurred with the standard MAT. The study concluded that the rLipL41 protein could be used as a potential diagnostic antigen in different assay formats for bovine leptospirosis.


Asunto(s)
Antígenos Bacterianos/inmunología , Enfermedades de los Bovinos/microbiología , Inmunoglobulina G/sangre , Leptospira/aislamiento & purificación , Leptospirosis/veterinaria , Animales , Antígenos Bacterianos/química , Bovinos , Enfermedades de los Bovinos/diagnóstico , Ensayo de Inmunoadsorción Enzimática/veterinaria , Pruebas de Fijación de Látex/veterinaria , Leptospira/inmunología , Leptospirosis/diagnóstico , Leptospirosis/microbiología , Proteínas Recombinantes/química , Proteínas Recombinantes/inmunología , Sensibilidad y Especificidad , Pruebas Serológicas
19.
Microbiology (Reading) ; 155(Pt 11): 3683-3690, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19684064

RESUMEN

Mycobacterium avium subspecies paratuberculosis (MAP), the causative agent of Johne's disease in cattle and sheep, has unique iron requirements in that it is mycobactin-dependent for cultivation in vitro. The iron-dependent regulator (IdeR) is a well-characterized global regulator responsible for maintaining iron homeostasis in Mycobacterium tuberculosis (MTB). We identified an orthologous segment in the MAP genome, MAP2827, with >93 % amino acid identity to MTB IdeR. Electrophoretic mobility shift assays and DNase protection assays confirmed that MAP2827 binds the 19 bp consensus motif (iron box) on the MAP genome. Sequencing of MAP2827 from multiple isolates revealed a non-synonymous change (R91G) exclusive to sheep strains. Reporter gene assays and quantitative real-time RT-PCR assays in two diverse MAP strains and in an ideR deletion mutant of M. smegmatis (mc(2)155) suggested that both sheep MAP IdeR (sIdeR) and cattle MAP IdeR (cIdeR) repress mbtB transcription at high iron concentrations and relieve repression at low iron concentrations. On the other hand, bfrA (an iron storage gene) was upregulated by cIdeR when presented with MTB or the cattle MAP bfrA promoter, and was downregulated by sIdeR in the presence of MTB, or sheep or cattle MAP bfrA promoters, at high iron concentrations. The differential iron regulatory mechanisms between IdeR-regulated genes across strains may contribute to the differential growth or pathogenic characteristics of sheep and cattle MAP strains. Taken together, our study provides a possible reason for mycobactin dependency and suggests strong implications in the differential iron acquisition and storage mechanisms in MAP.


Asunto(s)
Proteínas Bacterianas/metabolismo , Hierro/metabolismo , Mycobacterium avium subsp. paratuberculosis/genética , Proteínas Represoras/metabolismo , Animales , Proteínas Bacterianas/genética , Secuencia de Bases , Bovinos , Huella de ADN , ADN Bacteriano/genética , Ensayo de Cambio de Movilidad Electroforética , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos , Datos de Secuencia Molecular , Mycobacterium avium subsp. paratuberculosis/metabolismo , Regiones Promotoras Genéticas , Proteínas Represoras/genética , Ovinos
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