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1.
Plant Mol Biol ; 110(6): 545-563, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35997919

RESUMO

WD40 domain-containing proteins are one of the eukaryotes' most ancient and ubiquitous protein families. Little is known about the presence and function of these proteins in cyanobacteria in general and Anabaena in particular. In silico analysis confirmed the presence of WD40 repeats. Gene expression analysis indicated that the transcript levels of both the target proteins were up-regulated up to 4 fold in Cd and drought and 2-3 fold in heat, salt, and UV-B stress. Using a fluorescent oxidative stress indicator, we showed that the recombinant proteins were scavenging reactive oxygen species (ROS) (4-5 fold) more efficiently than empty vectors. Chromatin immunoprecipitation analysis (ChIP) and electrophoretic mobility shift assay (EMSA) revealed that the target proteins function as transcription factors after binding to the promoter sequences. The presence of kinase activity (2-4 fold) in the selected proteins indicated that these proteins could modulate the functions of other cellular proteins under stress conditions by inducing phosphorylation of specific amino acids. The chosen proteins also demonstrated interaction with Zn, Cd, and Cu (1.4-2.5 fold), which might stabilize the proteins' structure and biophysical functions under multiple abiotic stresses. The functionally characterized Alr0671 and All2352 proteins act as transcription factors and offer tolerance to agriculturally relevant abiotic stresses.


Alr0671 and All2352 are novel WD40 proteins of Anabaena capable of regulating biochemical functions and abiotic stress tolerance by acting as a transcription factor and mediating DNA-protein interaction.


Assuntos
Anabaena , Cádmio , Anabaena/genética , Estresse Fisiológico/genética , Secas , Fatores de Transcrição/genética , Proteínas de Plantas/genética
2.
Curr Genomics ; 21(4): 295-310, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33071622

RESUMO

BACKGROUND: Cyanobacteria are excellent model to understand the basic metabolic processes taking place in response to abiotic stress. The present study involves the characterization of a hypothetical protein Alr0765 of Anabaena PCC7120 comprising the CBS-CP12 domain and deciphering its role in abiotic stress tolerance. METHODS: Molecular cloning, heterologous expression and protein purification using affinity chromatography were performed to obtain native purified protein Alr0765. The energy sensing property of Alr0765 was inferred from its binding affinity with different ligand molecules as analyzed by FTIR and TNP-ATP binding assay. AAS and real time-PCR were applied to evaluate the iron acquisition property and cyclic voltammetry was employed to check the redox sensitivity of the target protein. Transcript levels under different abiotic stresses, as well as spot assay, CFU count, ROS level and cellular H2O2 level, were used to show the potential role of Alr0765 in abiotic stress tolerance. In-silico analysis of Alr0765 included molecular function probability analysis, multiple sequence analysis, protein domain and motif finding, secondary structure analysis, protein-ligand interaction, homologous modeling, model refinement and verification and molecular docking was performed with COFACTOR, PROMALS-3D, InterProScan, MEME, TheaDomEx, COACH, Swiss modeller, Modrefiner, PROCHECK, ERRAT, MolProbity, ProSA, TM-align, and Discovery studio, respectively. RESULTS: Transcript levels of alr0765 significantly increased by 20, 13, 15, 14.8, 12, 7, 6 and 2.5 fold when Anabaena PCC7120 treated with LC50 dose of heat, arsenic, cadmium, butachlor, salt, mannitol (drought), UV-B, and methyl viologen respectively, with respect to control (untreated). Heterologous expression resulted in 23KDa protein observed on the SDS-PAGE. Immunoblotting and MALDI-TOF-MS/MS, followed by MASCOT search analysis, confirmed the identity of the protein and ESI/MS revealed that the purified protein was a dimer. Binding possibility of Alr0765 with ATP was observed with an almost 6-fold increment in relative fluorescence during TNP-ATP binding assay with a λ max of 538 nm. FTIR spectra revealed modification in protein confirmation upon binding of Alr0765 with ATP, ADP, AMP and NADH. A 10-fold higher accumulation of iron was observed in digests of E. coli with recombinant vector after induction as compared to control, which affirms the iron acquisition property of the protein. Moreover, the generation of the redox potential of 146 mV by Alr0765 suggested its probable role in maintaining the redox status of the cell under environmental constraints. As per CFU count recombinant, E. coli BL21 cells showed about 14.7, 7.3, 6.9, 1.9, 3 and 4.9 fold higher number of colonies under heat, cadmium (CdCl2), arsenic (Na3AsO4), salt (NaCl), UV-B and drought (mannitol) respectively compared to pET21a harboring E. coli BL21 cells. Deterioration in the cellular ROS level and total cellular H2O2 concentration validated the stress tolerance ability of Alr0765. In-silico analysis unraveled novel findings and attested experimental findings in determining the role of Alr0765. CONCLUSION: Alr0765 is a novel CBS-CP12 domain protein that maintains cellular energy level and iron homeostasis which provides tolerance against multiple abiotic stresses.

3.
Plant Cell Physiol ; 60(5): 1025-1040, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30690505

RESUMO

To overcome the difficulties to analyze membrane desaturases at the protein level, transgenic Arabidopsis plants expressing the plastidial AtFAD7 and AtFAD8 ω-3 desaturases fused to green fluorescent protein, under the control of their endogenous promoters, were generated and their tissue relative abundance was studied. Gene expression, glucuronidase promoter activity, immunoblot and confocal microscopy analyses indicated that AtFAD7 is the major ω-3 desaturase in leaves when compared to AtFAD8. This higher abundance of AtFAD7 was consistent with its higher promoter activity and could be related with its specificity for the abundant leaf galactolipids. AtFAD7 was also present in roots but at much lower level than leaves. AtFAD8 expression and protein abundance in leaves was consistent with its lower promoter activity, suggesting that transcriptional control modulates the abundance of both desaturases in leaves. AtFAD7 protein levels increased in response to wounding but not to jasmonate (JA), and decreased upon abscisic acid (ABA) treatment. Conversely, AtFAD8 protein levels increased upon cold or JA exposure and decreased at high temperatures, but did not respond to ABA or wounding. These results indicated specific and non-redundant roles for the plastidial ω-3 desaturases in defense, temperature stress or phytohormone mediated responses and a tight coordination of their activities between biotic and abiotic stress signaling pathways. Our data suggested that transcriptional regulation was crucial for this coordination. Finally, bimolecular fluorescence complementation analysis showed that both AtFAD7 and AtFAD8 interact with the AtFAD6 ω-6 desaturase in vivo, suggesting that quaternary complexes are involved in trienoic fatty acid production within the plastid membranes.


Assuntos
Ácido Abscísico/farmacologia , Proteínas de Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Ciclopentanos/farmacologia , Ácidos Graxos Dessaturases/metabolismo , Oxilipinas/farmacologia , Plastídeos/efeitos dos fármacos , Plastídeos/metabolismo , Arabidopsis/fisiologia , Temperatura Baixa , Plastídeos/fisiologia
4.
Funct Integr Genomics ; 17(1): 39-52, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27778111

RESUMO

In silico derived properties on experimental validation revealed that hypothetical protein Alr2954 of Anabaena sp. PCC7120 is ADP-ribose pyrophosphatase, which belongs to nudix hydrolase superfamily. Presence of ADP-ribose binding site was attested by ADP-ribose pyrophosphatase activity (K m 44.71 ± 8.043 mM, V max 7.128 ± 0.417 µmol min-1 mg protein-1, and K cat/K m 9.438 × 104 µM-1 min-1). Besides ADP-ribose, the enzyme efficiently hydrolyzed various nucleoside phosphatases such as 8-oxo-dGDP, 8-oxo-dADP, 8-oxo-dGTP, 8-oxo-dATP, GDP-mannose, ADP-glucose, and NADH. qRT-PCR analysis of alr2954 showed significant expression under different abiotic stresses reconfirming its role in stress tolerance. Thus, Alr2954 qualifies to be a member of nudix hydrolase superfamily, which serves as ADP-ribose pyrophosphatase and assists in multiple abiotic stress tolerance.


Assuntos
Anabaena/enzimologia , Escherichia coli/genética , Pirofosfatases/genética , Estresse Fisiológico/genética , Adenosina Difosfato Ribose/química , Adenosina Difosfato Ribose/metabolismo , Sequência de Aminoácidos/genética , Sítios de Ligação , Clonagem Molecular , Simulação por Computador , Nucleotídeos de Desoxiadenina/metabolismo , Nucleotídeos de Desoxiguanina/metabolismo , Escherichia coli/enzimologia , Hidrólise , Simulação de Acoplamento Molecular , Pirofosfatases/química , Pirofosfatases/isolamento & purificação , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
5.
Funct Integr Genomics ; 17(4): 413-425, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28190210

RESUMO

Aldo/keto reductases (AKRs) constitute a multitasking protein family that catalyzes diverse metabolic transformations including detoxification of stress generated reactive aldehydes. Yet this important protein family is poorly understood particularly in cyanobacteria, the ecologically most diverse and significant group of micro-organisms. Present study is an attempt to characterize all putative AKRs of Anabaena sp. PCC 7120. In silico analysis, it revealed the presence of at least four putative AKRs in Anabaena PCC7120 genome. All four proteins share less than 40% sequence identity with each other and also with the identified members of AKR superfamily and hence deserve to be assigned in new families. Dissimilarity in sequences is also reflected through their substrate specificity. While reduction of trans-2-nonenal, a LPO-derived reactive aldehyde was common across the four proteins, these proteins were found to be activated during heat, salt, Cd, As, and butachlor treatments, and their ectopic expression in Escherichia coli conferred tolerance to the above abiotic stresses. These findings affirm the role of AKRs in providing a broad tolerance to environmental stresses conceivably by detoxifying the stress-generated reactive aldehydes.


Assuntos
Aldo-Ceto Redutases/genética , Anabaena/enzimologia , Proteínas de Bactérias/genética , Aldo-Ceto Redutases/química , Aldo-Ceto Redutases/metabolismo , Anabaena/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Homologia de Sequência , Especificidade por Substrato
6.
Funct Integr Genomics ; 15(1): 77-92, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25391500

RESUMO

In silico analysis together with cloning, molecular characterization and heterologous expression reports that the hypothetical protein All5371 of Anabaena sp. PCC7120 is a novel hydroperoxide scavenging protein similar to AhpD of bacteria. The presence of E(X)11CX HC(X)3H motif in All5371 confers peroxidase activity and closeness to bacterial AhpD which is also reflected by its highest 3D structure homology with Rhodospirillum rubrum AhpD. Heterologous expression of all5371 complimented for ahpC and conferred resistance in MJF178 strain (ahpCF::Km) of Escherichia coli. All5371 reduced the organic peroxide more efficiently than inorganic peroxide and the recombinant E. coli strain following exposure to H2O2, CdCl2, CuCl2, heat, UV-B and carbofuron registered increased growth over wild-type and mutant E. coli transformed with empty vector. Appreciable expression of all5371 in Anabaena sp. PCC7120 as measured by qRT-PCR under selected stresses and their tolerance against H2O2, tBOOH, CuOOH and menadione attested its role in stress tolerance. In view of the above, All5371 of Anabaena PCC7120 emerged as a new hydroperoxide detoxifying protein.


Assuntos
Adaptação Fisiológica , Anabaena/enzimologia , Escherichia coli/fisiologia , Peroxidases/metabolismo , Estresse Fisiológico , Sequência de Aminoácidos , Clonagem Molecular , Ativação Enzimática , Escherichia coli/genética , Teste de Complementação Genética , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Modelos Moleculares , Dados de Sequência Molecular , Mutação , NADP/metabolismo , Oxirredução , Peroxidase/metabolismo , Peroxidases/química , Peroxidases/isolamento & purificação , Filogenia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia Estrutural de Proteína , Especificidade por Substrato , Temperatura , Transformação Genética
7.
Funct Integr Genomics ; 13(1): 43-55, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23086594

RESUMO

In silico analysis followed by experimental validation leads us to propose that the predicted protein All0195 of Anabaena sp. PCC7120 showing enhanced expression under sodium arsenate (Na2HAsO4) stress belongs to the thioredoxin superfamily with structural similarity to bacterial arsenate reductase. The All0195 protein demonstrated C-X-TC-X-K, NTSG-X2-YR, and D-X2-L-X-KRP as functional motifs that show similarity to seven known bacterial arsenate reductase family protein homologs with Cys, Arg, and Pro as conserved residues. In view of physicochemical properties, such as aliphatic index, ratio of Glu + Lys to Gln + His, and secondary structure, it was evident that All0195 was also a thermostable protein. The predicted three-dimensional structure on molecular docking with arsenate oxyanion ([Formula: see text]) revealed its interaction with conserved Cys residue as also known for other bacterial arsenate reductase. In silico derived properties were experimentally attested by cloning and heterologous expression of all0195. Furthermore, this protein functionally complemented the arsenate reductase-deficient sodium arsenate-hypersensitive phenotype of Escherichia coli strainWC3110 (ΔarsC) and depicted arsenate reductase activity on purification. In view of the above properties, All0195 appears to be a new arsenate reductase involved in arsenic detoxification in Anabaena sp. PCC7120.


Assuntos
Anabaena/enzimologia , Arseniato Redutases/metabolismo , Arseniatos/toxicidade , Proteínas de Bactérias/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Anabaena/genética , Arseniato Redutases/química , Arseniato Redutases/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Domínio Catalítico , Sequência Conservada , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Estrutura Terciária de Proteína
8.
Photosynth Res ; 118(1-2): 105-14, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24113924

RESUMO

This study examines response of Anabaena sp. PCC 7120 to salt and UV-B stress by combining physiological, biochemical, proteomics and bioinformatics approaches. Sixty five significantly altered protein spots corresponding to 51 protein genes identified using MALDI-TOF MS/MS were divided into nine functional categories. Based on relative abundance, these proteins were grouped into four major sets. Of these, 27 and 5 proteins were up- and downregulated, respectively, both under salt and UV-B while 8 and 11 proteins showed accumulation in salt and UV-B applied singly. Some responses common to salt and UV-B included (i) enhanced expression of FeSOD, alr3090 and accumulation of MDA indicating oxidative stress, (ii) accumulation of PDH, G6P isomerase, FBPaldolase, TK, GAPDH and PGK suggesting enhanced glycolysis, (iii) upregulation of 6-PGD, 6PGL and NADPH levels signifying operation of pentose phosphate pathway, (iv) upregulation of Dps, NDK and alr3199 indicating DNA damage, and (v) accumulation of proteins of ribosome assembly, transcriptional and translational processing. In contrast, enhanced expression of RUBISCO, increased glycolate oxidase activity and ammonium content under salt signify the difference. Salt was found to be more damaging than UV-B probably due to a cumulative effect of ionic, osmotic and oxidative damage. A group of proteins having common expression represent decreased toxicity of salt and UV-B when applied in combination.


Assuntos
Anabaena/metabolismo , Anabaena/efeitos da radiação , Salinidade , Perfilação da Expressão Gênica , Proteômica , Cloreto de Sódio , Estresse Fisiológico , Raios Ultravioleta
9.
Int J Biol Macromol ; 233: 123563, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36746302

RESUMO

Cyanobacterial DnaJ offers thermo-tolerance and effectively prevents aggregation of denatured protein in coordination with DnaK. The hypothetical protein All3048 of Anabaena sp. PCC7120 was found to be a 24 kDa DnaJ III protein with a putative J-domain at the extreme N-terminus. This paper decodes the role of All3048 in thermo-tolerance and as a co-chaperon of DnaK. Semi-quantitative and RT-PCR results showed up-accumulation of all3048 in heat, UV-B, cadmium, arsenic and salt. BL21/pET-28a-all3048, all3048(1-95) and all3048(31-128) reduced the heat stress-induced ROS generation by 40 %, 21 % and 24 % as compared to BL21/pET-28-a. Conformational properties of All3048 and its truncated variants were assessed using bis ANS, guanidine hydrochloride and acrylamide quenching. All3048(1-95), All3048 and All3048(31-128) increased DnaK ATPase activity by 8.6, 8.2, and 2.5 fold, respectively. The thermostability investigated using DSC and DSF methods affirmed the relative stability of All3048 and All3048 (31-128), whereas All3048 (1-95) was the least stable. All3048 is a novel cyanobacterial DnaJ III that imparts heat stress tolerance in E. coli; however, only the J-domain present at N-terminus was sufficient for stimulating DnaK's ATPase activity.


Assuntos
Anabaena , Proteínas de Escherichia coli , Escherichia coli/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Resposta ao Choque Térmico , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Anabaena/genética , Anabaena/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
10.
Biometals ; 25(5): 893-903, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22592442

RESUMO

Trace metals are required for many cellular processes. The acquisition of trace elements from the environment includes a rapid adsorption of metals to the cell surface, followed by a slower internalization. We investigated the uptake of the trace elements Co(2+), Cu(2+), Mn(2+), Ni(2+), and Zn(2+) and the non-essential divalent cation Cd(2+) in the cyanobacterium Nostoc punctiforme. For each metal, a dose response study based on cell viability showed that the highest non-toxic concentrations were: 0.5 µM Cd(2+), 2 µM Co(2+), 0.5 µM Cu(2+), 500 µM Mn(2+), 1 µM Ni(2+), and 18 µM Zn(2+). Cells exposed to these non-toxic concentrations with combinations of Zn(2+) and Cd(2+), Zn(2+) and Co(2+), Zn(2+) and Cu(2+) or Zn(2+) and Ni(2+), had reduced growth in comparison to controls. Cells exposed to metal combinations with the addition of 500 µM Mn(2+) showed similar growth compared to the untreated controls. Metal levels were measured after one and 72 h for whole cells and absorbed (EDTA-resistant) fractions and used to calculate differential uptake rates for each metal. The differences in binding and internalisation between different metals indicate different uptake processes exist for each metal. For each metal, competitive uptake experiments using (65)Zn showed that after 72 h of exposure Zn(2+) uptake was reduced by most metals particularly 0.5 µM Cd(2+), while 2 µM Co(2+) increased Zn(2+) uptake. This study demonstrates that N. punctiforme discriminates between different metals and favourably substitutes their uptake to avoid the toxic effects of particular metals.


Assuntos
Metais/farmacocinética , Nostoc/metabolismo , Ligação Competitiva , Biodegradação Ambiental , Cátions Bivalentes/farmacocinética , Cátions Bivalentes/toxicidade , Transporte de Íons , Metais/toxicidade , Viabilidade Microbiana/efeitos dos fármacos , Nostoc/efeitos dos fármacos , Oligoelementos/farmacocinética , Oligoelementos/toxicidade
11.
Genet Couns ; 23(4): 487-91, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23431749

RESUMO

Maternal systemic lupus erythematosus and autoimmune diseases have been extremely rarely reported to cause rhizomelic chondrodysplasia punctata. We report on a fetus aborted spontaneously at 21 weeks of gestation due to complications of maternal mixed connective tissue disorder. The fetus had micrognathia, a depressed nasal bridge, flat nose, long philtrum, short columella and rhizomelia. Radiographic study showed stippling of carpal and tarsal bones, short humeri and coronal clefts in the vertebrae. Ossification centers were present at the lower end of the femora and upper end of the tibiae.


Assuntos
Anormalidades Múltiplas/etiologia , Condrodisplasia Punctata Rizomélica/etiologia , Doenças Fetais/etiologia , Doença Mista do Tecido Conjuntivo/complicações , Complicações na Gravidez , Anormalidades Múltiplas/diagnóstico , Aborto Espontâneo , Adulto , Ossos do Carpo/anormalidades , Ossos do Carpo/diagnóstico por imagem , Condrodisplasia Punctata Rizomélica/diagnóstico , Feminino , Doenças Fetais/diagnóstico , Feto , Humanos , Masculino , Micrognatismo/diagnóstico , Micrognatismo/etiologia , Gravidez , Radiografia , Índice de Gravidade de Doença , Ossos do Tarso/anormalidades , Ossos do Tarso/diagnóstico por imagem
12.
Nat Commun ; 13(1): 1690, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35354803

RESUMO

Cyclophilins, or immunophilins, are proteins found in many organisms including bacteria, plants and humans. Most of them display peptidyl-prolyl cis-trans isomerase activity, and play roles as chaperones or in signal transduction. Here, we show that cyclophilin anaCyp40 from the cyanobacterium Anabaena sp. PCC 7120 is enzymatically active, and seems to be involved in general stress responses and in assembly of photosynthetic complexes. The protein is associated with the thylakoid membrane and interacts with phycobilisome and photosystem components. Knockdown of anacyp40 leads to growth defects under high-salt and high-light conditions, and reduced energy transfer from phycobilisomes to photosystems. Elucidation of the anaCyp40 crystal structure at 1.2-Å resolution reveals an N-terminal helical domain with similarity to PsbQ components of plant photosystem II, and a C-terminal cyclophilin domain with a substrate-binding site. The anaCyp40 structure is distinct from that of other multi-domain cyclophilins (such as Arabidopsis thaliana Cyp38), and presents features that are absent in single-domain cyclophilins.


Assuntos
Cianobactérias , Ficobilissomas , Cianobactérias/metabolismo , Ciclofilinas/genética , Ciclofilinas/metabolismo , Humanos , Complexo de Proteína do Fotossistema II/metabolismo , Ficobilissomas/metabolismo , Tilacoides/metabolismo
13.
Plant Physiol Biochem ; 168: 353-372, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34700048

RESUMO

Oxidative stress is common consequence of abiotic stress in plants as well as cyanobacteria caused by generation of reactive oxygen species (ROS), an inevitable product of respiration and photosynthetic electron transport. ROS act as signalling molecule at low concentration however, when its production exceeds the endurance capacity of antioxidative defence system, the organisms suffer oxidative stress. A highly toxic metabolite, methylglyoxal (MG) is also produced in cyanobacteria in response to various abiotic stresses which consequently augment the ensuing oxidative damage. Taking recourse to the common lineage of eukaryotic plants and cyanobacteria, it would be worthwhile to explore the regulatory role of glyoxalase system and antioxidative defense mechanism in combating abiotic stress in cyanobacteria. This review provides comprehensive information on the complete glyoxalase system (GlyI, GlyII and GlyIII) in cyanobacteria. Furthermore, it elucidates the recent understanding regarding the production of ROS and MG, noteworthy link between intracellular MG and ROS and its detoxification via synchronization of antioxidants (enzymatic and non-enzymatic) and glyoxalase systems using glutathione (GSH) as common co-factor.


Assuntos
Antioxidantes , Cianobactérias , Plantas , Aldeído Pirúvico , Espécies Reativas de Oxigênio
14.
Genet Couns ; 21(2): 233-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20681225

RESUMO

Unusual facial cleft in Fryns syndrome: defect of stomodeum?: We report on a fetus with Fryns syndrome. The facial cleft was unusual. There was bilateral cleft lip with cleft palate. The intermaxillary segment was connected through the base of a mound in the midline to the lower lip. We believe this is an atypical facial cleft in Fryns syndrome and likely represents a defective stomodeum.


Assuntos
Anormalidades Múltiplas , Face/anormalidades , Doenças Fetais , Fenda Labial , Síndrome de Dandy-Walker , Hérnias Diafragmáticas Congênitas , Humanos , Masculino , Síndrome
16.
Appl Environ Microbiol ; 75(3): 784-91, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19011078

RESUMO

Zinc homeostasis was investigated in Nostoc punctiforme. Cell tolerance to Zn(2+) over 14 days showed that ZnCl(2) levels above 22 microM significantly reduced cell viability. After 3 days in 22 microM ZnCl(2), ca. 12% of the Zn(2+) was in an EDTA-resistant component, suggesting an intracellular localization. Zinquin fluorescence was detected within cells exposed to concentrations up to 37 microM relative to 0 microM treatment. Radiolabeled (65)Zn showed Zn(2+) uptake increased over a 3-day period, while efflux occurred more rapidly within a 3-h time period. Four putative genes involved in Zn(2+) uptake and efflux in N. punctiforme were identified: (i) the predicted Co/Zn/Cd cation transporter, putative CDF; (ii) the predicted divalent heavy-metal cation transporter, putative Zip; (iii) the ATPase component and Fe/Zn uptake regulation protein, putative Fur; and (iv) an ABC-type Mn/Zn transport system, putative zinc ZnuC, ZnuABC system component. Quantitative real-time PCR indicated the responsiveness of all four genes to 22 microM ZnCl(2) within 3 h, followed by a reduction to below basal levels after 24 h by putative ZIP, ZnuC, and Fur and a reduction to below basal level after 72 h by putative CDF efflux gene. These results demonstrate differential regulation of zinc transporters over time, indicating a role for them in zinc homeostasis in N. punctiforme.


Assuntos
Biologia Computacional , Perfilação da Expressão Gênica , Homeostase , Nostoc/genética , Nostoc/metabolismo , Zinco/metabolismo , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Viabilidade Microbiana , Nostoc/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Zinco/toxicidade
17.
Med J Malaysia ; 64(4): 303-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20954555

RESUMO

To evaluate the perinatal outcome of premature babies according to the mode of delivery. A total of 113 pregnant women and 124 neonates who delivered from 30 to 35 weeks of gestation were enrolled and outcomes of 70 neonates born vaginally were compared to 54 neonates born by caesarean. Neonatal mortality rate was 20 percent for infants in caesarean group as compared to 10 percent for vaginal group. There was no significant difference in the neonatal morbidity among both the groups. Caesarean delivery cannot be routinely recommended, unless there are obstetric indications.


Assuntos
Parto Obstétrico/métodos , Nascimento Prematuro , Adolescente , Adulto , Cesárea/estatística & dados numéricos , Feminino , Humanos , Mortalidade Infantil , Recém-Nascido , Morbidade , Gravidez
18.
Aquat Toxicol ; 214: 105238, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301544

RESUMO

Abiotic stresses enhance the cellular level of reactive oxygen species (ROS) which consequently leads to toxic methylglyoxal (MG) production. Glyoxalases (GlyI & GlyII) catalyze the conversion of toxic MG into non-toxic lactic acid but their properties and functions have been overlooked in cyanobacteria. This is the first attempt to conduct a genome-wide analysis of GlyI protein (PF00903) from Anabaena sp. PCC7120. Out of total nine GlyI domain possessing proteins, only three (Alr2321, Alr4469, All1022) harbour conserve His/Glu/His/Glu metal binding site at their homologous position and are deficient in conserved region specific for Zn2+ dependent members. Their biochemical, structural and functional characterization revealed that only Alr2321 is a homodimeric Ni2+ dependent active GlyI with catalytic efficiency 11.7 × 106 M-1 s-1. It has also been found that Alr2321 is activated by various divalent metal ions and has maximum GlyI activity with Ni2+ followed by Co2+ > Mn2+ > Cu2+ and no activity with Zn2+. Moreover, the expression of alr2321 was found to be maximally up-regulated under heat (19 fold) followed by cadmium, desiccation, arsenic, salinity and UV-B stresses. BL21/pGEX-5X2-alr2321 showed improved growth under various abiotic stresses as compared to BL21/pGEX-5X2 by increased scavenging of intracellular MG and ROS levels. Taken together, these results suggest noteworthy links between intracellular MG and ROS, its detoxification by Alr2321, a member of GlyI family of Anabaena sp. PCC7120, in relation to abiotic stress.


Assuntos
Anabaena/enzimologia , Lactoilglutationa Liase/metabolismo , Aldeído Pirúvico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , Motivos de Aminoácidos , Sequência de Aminoácidos , Anabaena/efeitos dos fármacos , Inativação Metabólica/efeitos dos fármacos , Cinética , Lactoilglutationa Liase/química , Lactoilglutationa Liase/genética , Metais/farmacologia , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homologia Estrutural de Proteína , Especificidade por Substrato/efeitos dos fármacos
19.
Int J Biol Macromol ; 124: 981-993, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30468810

RESUMO

Abiotic stresses enhance cellular reactive oxygen species (ROS) level which results in toxic methylglyoxal (MG) production. Glyoxalases catalyze the conversion of toxic MG into non-toxic lactic acid whose properties and function are still unknown in cyanobacteria. This is the first attempt to characterize All0580 from Anabaena sp. PCC7120 as GlyII using in silico and wet lab approaches. Data of functional complementation of E. coli GlyII mutant (ΔgloB), enzyme kinetics and ESI-MS analysis suggested that All0580 harbors distinctive GlyII activity. The catalytic efficiency of All0580 (3 × 106 M-1 s-1) is higher than Arabidopsis GlyII. AAS analysis revealed the presence of a binuclear Zn/Fe centre in All0580 active site. The qRT-PCR of the target gene revealed maximum up-regulation in salinity followed by drought, arsenic, heat, and UV-B stresses. BL21/pET-21a-all0580 showed 1.5 to 10 fold increased growth and up to 4 fold decreased intracellular MG level as compared to BL21/pET-21a cells under various abiotic stresses and MG. A 39% drop in ROS generation by BL21/pET-21a-all0580 under MG stress suggested its potential to manage MG toxicity. Above attributes suggest that the hypothetical protein All0580 is a novel GlyII of cyanobacteria which heterologously confers tolerance to multiple abiotic stresses in E. coli.


Assuntos
Anabaena , Proteínas de Bactérias , Escherichia coli , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , Tioléster Hidrolases , Anabaena/enzimologia , Anabaena/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Escherichia coli/enzimologia , Escherichia coli/genética , Tioléster Hidrolases/biossíntese , Tioléster Hidrolases/genética
20.
Gene ; 685: 230-241, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30448320

RESUMO

In- silico and functional genomics approaches have been used to determine cellular functions of two hypothetical proteins All1122 and Alr0750 of Anabaena sp. PCC 7120. Motif analysis and multiple sequence alignment predicted them as typical α/ß ATP binding universal stress family protein-A (UspA) with G-(2×)-G-(9×)-G(S/T) as conserved motif. qRT-PCR data under UV-B, NaCl, heat, As, CdCl2, mannitol and methyl viologen registered approximately 1.4 to 4.3 fold induction of all1122 and alr0750 thus confirming their multiple abiotic stress tolerance potential. The recombinant E. coli (BL21) cells harboring All1122 and Alr0750 showed 12-41% and 23-41% better growth respectively over wild type control under said abiotic stresses thus revalidating their stress coping ability. Functional complementation on heterologous expression in UspA mutant E. coli strain LN29MG1655 (ΔuspA::Kan) attested their UspA family membership. This study tempted us to suggest that recombinant Anabaena PCC 7120 over expressing all1122 and alr0750 might contribute to the nitrogen economy in paddy fields experiencing array of abiotic stresses including drought and nutrient limitation.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cianobactérias/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Estresse Fisiológico/genética , Proteínas de Bactérias/química , Clonagem Molecular , Cianobactérias/genética , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Ligantes , Modelos Moleculares , Filogenia , Conformação Proteica
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