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1.
Environ Monit Assess ; 196(5): 488, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687382

RESUMO

Clean water is essential for drinking, household use, and agriculture. Researchers studied 39 sites near Tamla nala and Nunia nala channels in Durgapur and Asansol City (West Bengal) to assess the deterioration level of water due to industrial discharge. During the first phase out of three, the researchers conducted a spatial representation of various physicochemical parameters, such as temperature, pH, Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Total Hardness (TH), Electrical Conductivity (EC), Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), significant anions such as chloride (Cl-), nitrate (NO3-), phosphate (PO4-3), sulfate (SO42-), cyanide (CN-1) and fluoride (F-), as well as heavy metals/metalloids such as lead (Pb), cadmium (Cd), chromium (Cr), iron (Fe), copper (Cu), nickel (Ni), mercury (Hg) and arsenic (As). As observed the parameters at various sites along the stream exceeded threshold limits majorly due to industrial discharge: highest pH, TDS, TH, EC, Cl-, SO42- at site 26; Fe at site 1, TSS, COD, CN- at site 33, 31, 2 respectively; Cd, Ni, Cu at site 19; Hg and Pb at site 3 and As at site 20. Contaminated areas were marked in red and secure areas in green. Additionally, the HMPI (Heavy metal pollution index) was estimated for eight locations to understand the impact of heavy metal pollution in the second phase of the study. An extremely high HMPI indicates heightened toxicity and health risks for both residents and outsiders. The Canadian Water Quality Index (1.0) was calculated for eight sites in the third phase based on seventeen parameters. The resulting WQI value was below 44, indicating poor water quality at the sites. Due to the poor quality and critical heavy metal toxicity, the authors recommended continuous monitoring, strict regulation enforcement, increased treatment capacity, Zero Liquid Discharge implementation, and raising awareness among residents.


Assuntos
Monitoramento Ambiental , Metais Pesados , Rios , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Metais Pesados/análise , Rios/química , Índia , Análise da Demanda Biológica de Oxigênio , Resíduos Industriais/análise
2.
Biochem Biophys Rep ; 4: 59-75, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29124188

RESUMO

BACKGROUNDS: Spontaneous deamidation and isoaspartate (IsoAsp) formation contributes to aging and reduced longevity in cells. A protein-l-isoaspartate (d-aspartate) O-methyltransferase (PCMT) is responsible for minimizing IsoAsp moieties in most organisms. METHODS: PCMT was purified in its native form from yeast Candida utilis. The role of the native PCMT in cell survival and protein repair was investigated by manipulating intracellular PCMT levels with Oxidized Adenosine (AdOx) and Lithium Chloride (LiCl). Proteomic Identification of possible cellular targets was carried out using 2-dimensional gel electrophoresis, followed by on-Blot methylation and mass spectrometric analysis. RESULTS: The 25.4 kDa native PCMT from C. utilis was found to have a Km of 3.5 µM for AdoMet and 33.36 µM for IsoAsp containing Delta Sleep Inducing Peptide (DSIP) at pH 7.0. Native PCMT comprises of 232 amino acids which is coded by a 698 bp long nucleotide sequence. Phylogenetic comparison revealed the PCMT to be related more closely with the prokaryotic homologs. Increase in PCMT levels in vivo correlated with increased cell survival under physiological stresses. PCMT expression was seen to be linked with increased intracellular reactive oxygen species (ROS) concentration. Proteomic identification of possible cellular substrates revealed that PCMT interacts with proteins mainly involved with cellular housekeeping. PCMT effected both functional and structural repair in aged proteins in vitro. GENERAL SIGNIFICANCE: Identification of PCMT in unicellular eukaryotes like C. utilis promises to make investigations into its control machinery easier owing to the familiarity and flexibility of the system.

3.
Biochim Biophys Acta ; 1840(6): 1861-71, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24412193

RESUMO

BACKGROUND: In Saccharomyces cerevisiae methylation at cysteine residue displayed enhanced activity of trehalose-6-phosphate synthase (TPS). METHODS: The cysteine methyltransferase (CMT) responsible for methylating TPS was purified and characterized. The amino acid sequence of the enzyme protein was determined by a combination of N-terminal sequencing and MALDI-TOF/TOF analysis. The nucleotide sequence of the CMT gene was determined, isolated from S. cerevisiae and expressed in E. coli. Targeted disruption of the CMT gene by PCR based homologous recombination in S. cerevisiae was followed by metabolite characterization in the mutant. RESULTS: The purified enzyme was observed to enhance the activity of TPS by a factor of 1.76. The 14kDa enzyme was found to be cysteine specific. The optimum temperature and pH of enzyme activity was calculated as 30°C and 7.0 respectively. The Km Vmax and Kcat against S-adenosyl-l-methionine (AdoMet) were 4.95µM, 3.2U/mg and 6.4s(-1) respectively. Competitive inhibitor S-Adenosyl-l-homocysteine achieved a Ki as 10.9µM against AdoMet. The protein sequence contained three putative AdoMet binding motifs. The purified recombinant CMT activity exhibited similar physicochemical characteristics with the native counterpart. The mutant, Mataα, cmt:: kan(r) exhibited almost 50% reduction in intracellular trehalose concentration. CONCLUSION: A novel cysteine methyltransferase is purified, which is responsible for enhanced levels of trehalose in S. cerevisiae. GENERAL SIGNIFICANCE: This is the first report about a cysteine methyltransferase which performs S methylation at cysteine residue regulating TPS activity by 50%, which resulted in an increase of the intercellular stress sugar, trehalose.


Assuntos
Cisteína/metabolismo , Glucosiltransferases/metabolismo , Metiltransferases/isolamento & purificação , Saccharomyces cerevisiae/enzimologia , Sequência de Aminoácidos , Clonagem Molecular , Escherichia coli/genética , Metilação , Metiltransferases/química , Metiltransferases/genética , Dados de Sequência Molecular , Especificidade por Substrato , Trealose/metabolismo
4.
J Cell Physiol ; 229(9): 1245-55, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24446217

RESUMO

Trehalose-6-phosphate phosphatase (TPP) catalyzes the final step in the biosynthesis of the anti-stress sugar trehalose. An 82 kDa TPP enzyme was isolated from Candida utilis with 61% yield and 43-fold purification. The protein sequence, determined by N-terminal sequencing and MALDI-TOF analysis, showed significant homology with known TPP sequences from related organisms. The full length gene sequence of TPP of C. utilis was identified using rapid amplification of cDNA ends-PCR reaction (RACE-PCR). The gene was cloned and expressed in Escherichia coli BL21. Recombinant TPP enzyme was isolated using affinity chromatography. CD spectroscopy and steady-state fluorescence revealed that the structural and conformational aspects were identical in both native and recombinant forms. The biochemical properties of the two forms were also similar. Km was determined to be ~0.8 mM. Optimum temperature and pH were found to be 30 °C and 8.5, respectively. Activity was dependent on the presence of divalent cations and inhibited by metal chelators. Methylation-mediated regulation of TPP enzyme and its effect on the overall survival of the organism under stress were investigated. The results indicated that enhancement of TPP activity by methylation at the Cysteine residues increased resistance of Candida cells against thermal stress. This work involves extensive investigations toward understanding the physico-chemical properties of the first TPP enzyme from any yeast strain. The mechanism by which methylation regulates its activity has also been studied. A correlation between regulation of trehalose synthesis and survivability of the organism under thermal stress was established.


Assuntos
Candida/enzimologia , Proteínas Fúngicas/metabolismo , Resposta ao Choque Térmico , Monoéster Fosfórico Hidrolases/metabolismo , Trealose/biossíntese , Sequência de Aminoácidos , Candida/genética , Quelantes/farmacologia , Cromatografia de Afinidade , Dicroísmo Circular , Clonagem Molecular , Inibidores Enzimáticos/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Concentração de Íons de Hidrogênio , Cinética , Metilação , Dados de Sequência Molecular , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Monoéster Fosfórico Hidrolases/química , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/isolamento & purificação , Conformação Proteica , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes/metabolismo , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Temperatura
5.
Psychiatr Serv ; 64(7): 660-5, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23584674

RESUMO

OBJECTIVE: This article describes the characteristics and early implementation experiences of community behavioral health agencies that received Primary and Behavioral Health Care Integration (PBHCI) grants from the Substance Abuse and Mental Health Services Administration to integrate primary care into programs for adults with serious mental illness. METHODS: Data were collected from 56 programs, across 26 states, that received PBHCI grants in 2009 (N=13) or 2010 (N=43). The authors systematically extracted quantitative and qualitative information about program characteristics from grantee proposals and semistructured telephone interviews with core program staff. Quarterly reports submitted by grantees were coded to identify barriers to implementing integrated care. RESULTS: Grantees shared core features required by the grant but varied widely in terms of characteristics of the organization, such as size and location, and in the way services were integrated, such as through partnerships with a primary care agency. Barriers to program implementation at start-up included difficulty recruiting and retaining qualified staff and issues related to data collection and use of electronic health records, licensing and approvals, and physical space. By the end of the first year, some problems, such as space issues, were largely resolved, but other issues, including problems with staffing and data collection, remained. New challenges, such as patient recruitment, had emerged. CONCLUSIONS: Early implementation experiences of PBHCI grantees may inform other programs that seek to integrate primary care into behavioral health settings as part of new, large-scale government initiatives, such as specialty mental health homes.


Assuntos
Serviços Comunitários de Saúde Mental/organização & administração , Prestação Integrada de Cuidados de Saúde/organização & administração , Pesquisa sobre Serviços de Saúde , Transtornos Mentais/terapia , Atenção Primária à Saúde/organização & administração , Adulto , Feminino , Implementação de Plano de Saúde/organização & administração , Apoio ao Planejamento em Saúde , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Seleção de Pessoal , Avaliação de Programas e Projetos de Saúde , Encaminhamento e Consulta , Estados Unidos , United States Substance Abuse and Mental Health Services Administration
6.
Carbohydr Res ; 361: 175-81, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23026712

RESUMO

Trehalose metabolism plays a central role in various stress responses in yeasts. Methylation dependant enhancement of trehalose synthesis has been reported from yeast Saccharomyces cerevisiae. In order to establish the role of methylation on trehalose metabolism in yeast, it was further investigated in Candida utilis. Universal methyl group donor, S-adenosyl-l-methionine (AdoMet) and its inhibitor, oxidized adenosine (Adox) were used to study the effect of methylation on trehalose metabolism in C. utilis. Treatment of early stationary phase cells of C. utilis with AdoMet and Adox exhibited increase in both intracellular metabolite levels and activities of the trehalose synthesizing enzymes, trehalose-6-phosphate synthase (TPS) and trehalose phosphate phosphatase (TPP). Among the intracellular metabolites studied, trehalose levels were enhanced in presence of AdoMet which correlated with the increasing levels of trehalose synthesizing enzymes. TPS was purified in presence of AdoMet and Adox, following an established protocol reported from this laboratory. Differences in the mobility of control TPS, methylated TPS, and methylation-inhibited TPS during acidic native gel electrophoresis confirmed the occurrence of induced methylation. MALDI-TOF analysis of trypsin-digested samples of the same further strengthened the presence of methylation in TPS. The data presented in this paper strongly indicate a positive role of methylation on trehalose synthesis which finally leads to enhanced trehalose production during the stationary growth phase of C. utilis.


Assuntos
Candida/metabolismo , Trealose/biossíntese , Candida/citologia , Glucosiltransferases/isolamento & purificação , Glucosiltransferases/metabolismo , Metilação , Fatores de Tempo , Trealose/química , Trealose/metabolismo
7.
Appl Biochem Biotechnol ; 168(8): 2358-75, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23070717

RESUMO

The present study explored both spontaneous and stress-induced deamidation in acid trehalase and endo-xylanase. An alteration in optimum pH by 1.5 units and optimum temperature by 20 °C accelerated the process of deamidation with a rise in isoaspartate formation and ammonia loss. Spontaneous deamidation during an enzyme-substrate reaction at physiological conditions resulted in accretion of isoaspartyl residues within the enzymes which gradually impaired their catalytic efficacy. Deamidation appeared to be more pronounced in endo-xylanase owing to its secondary structure conformation and high asparagine content. The active sites, Ala 549 in acid trehalase and His184 and Trp188 in endo-xylanase contributed to the loss of enzyme activity as they were flanking the deamidation-susceptible Asn residues. Protein L-isoaspartyl methyl transferase seemed to have a repairing capability, which enabled the heat-damaged enzymes to regain their partial activity as evident from there rise in K (cat)/K (m). Endo-xylanase could regain 38.1 % of its biological activity while a lesser 17.5 % reactivation was obtained in acid trehalase. A unique protein L-isoaspartyl methyl transferase recognition site, Asn 151 was also identified in acid trehalase. A mass increment of the tryptic peptides of repaired enzyme due to methylation catalyzed by protein L-isoaspartyl methyl transferase substantiated the repair hypothesis.


Assuntos
Amidas/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Proteína D-Aspartato-L-Isoaspartato Metiltransferase/metabolismo , Trealase/metabolismo , Sequência de Aminoácidos , Basidiomycota/enzimologia , Domínio Catalítico , Endo-1,4-beta-Xilanases/química , Concentração de Íons de Hidrogênio , Metilação , Modelos Moleculares , Dados de Sequência Molecular , Proteína D-Aspartato-L-Isoaspartato Metiltransferase/química , Saccharomyces cerevisiae/enzimologia , Temperatura , Trealase/química
8.
Arch Biochem Biophys ; 522(2): 90-9, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22484163

RESUMO

Trehalose and sucrose, two important anti-stress non-reducing natural disaccharides, are catabolized by two enzymes, namely trehalase and invertase respectively. In this study, a 175 kDa enzyme protein active against both substrates was purified from wild type Candida utilis and characterized in detail. Substrate specificity assay and activity staining revealed the enzyme to be specific for both sucrose and trehalose. The ratio between trehalase and invertase activity was found to be constant at 1:3.5 throughout the entire study. Almost 40-fold purification and 30% yield for both activities were achieved at the final step of purification. The presence of common enzyme inhibitors, thermal and pH stress had analogous effects on its trehalase and invertase activity. Km values for two activities were similar while Vmax and Kcat also differed by a factor of 3.5. Competition plot for both substrates revealed the two activities to be occurring at the single active site. N-terminal sequencing and MALDI-TOF data analysis revealed higher similarity of the purified protein to previously known neutral trehalases. While earlier workers mentioned independent purification of neutral trehalase or invertase from different sources, the present study reports the purification of a single protein showing dual activity.


Assuntos
Candida/enzimologia , Trealase/isolamento & purificação , beta-Frutofuranosidase/isolamento & purificação , Sequência de Aminoácidos , Domínio Catalítico , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Cinética , Reação em Cadeia da Polimerase , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Especificidade por Substrato , Trealase/antagonistas & inibidores , Trealase/química , Trealase/metabolismo , beta-Frutofuranosidase/antagonistas & inibidores , beta-Frutofuranosidase/química , beta-Frutofuranosidase/metabolismo
9.
J Cell Physiol ; 226(1): 158-64, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20648561

RESUMO

The current study was undertaken to correlate post-translational protein modification by methylation with the functionality of enzymes involved in trehalose metabolism in Saccharomyces cerevisiae. Trehalose is an economically important disaccharide providing protection against various kinds of stresses. It also acts as a source of cellular energy by storing glucose. Methyl group donor S-adenosyl L-methionine (AdoMet) and methylation inhibitor-oxidized adenosine (AdOx) were used for the methylation study. AdoMet delayed initial growth of the cells but the overall growth rate remained same suggesting its interference in G1 phase of the cell cycle. Metabolic-altered enzyme activities of acid trehalase (AT), neutral trehalase (NT), and trehalose-6-phosphate synthase (TPS) were observed when treated with AdOx and AdoMet separately. A positive effect of methylation was observed in TPS, hence, it was purified in three different conditions, using AdoMet, AdOx, and control. Differences in mobility of methylated, methylation-inhibited, and control TPS during acidic native gel electrophoresis confirmed the occurrence of induced methylation. Hydrolysis under alkaline pH conditions revealed that methylation of TPS was different than O-methylation. MALDI-TOF analysis of trypsin-digested samples of purified methylated, methylation-inhibited, and control TPS revealed that an increase of 18 Da mass in methylated peptides suggesting the introduction of methyl ester in TPS. Results of amino acid analysis corroborated the presence of methyl cysteine. The data presented here strongly suggests that trehalose production was enhanced due to methylation of TPS arising from carboxymethylation of cysteine residues.


Assuntos
Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Trealose/metabolismo , Adenosina/farmacologia , Proliferação de Células/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/fisiologia , Concentração de Íons de Hidrogênio , Metilação , Processamento de Proteína Pós-Traducional , S-Adenosilmetionina/farmacologia , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Tempo
10.
Biochim Biophys Acta ; 1790(5): 368-74, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19289151

RESUMO

Purified trehalose-6-phosphate synthase (TPS) of Saccharomyces cerevisiae was effective over a wide range of substrates, although differing with regard to their relative activity. Polyanions heparin and chondroitin sulfate were seen to stimulate TPS activity, particularly when a pyrimidine glucose nucleotide like UDPG was used, rather than a purine glucose nucleotide like GDPG. A high V(max) and a low K(m) value of UDPG show its greater affinity with TPS than GDPG or TDPG. Among the glucosyl acceptors TPS showed maximum activity with G-6-P which was followed by M-6-P and F-6-P. Effect of heparin was also extended to the purification of TPS activity, as it helped to retain both stability and activity of the final purified enzyme. Metal co-factors, specifically MnCl(2) and ZnCl(2) acted as stimulators, while enzyme inhibitors had very little effect on TPS activity. Metal chelators like CDTA, EGTA stimulated enzyme activity by chelation of metal inhibitors. Temperature and pH optima of the purified enzyme were determined to be 40 degrees C and pH 8.5 respectively. Enzyme activity was stable at 0-40 degrees C and at alkaline pH.


Assuntos
Glucosiltransferases/metabolismo , Saccharomyces cerevisiae/enzimologia , Quelantes/farmacologia , Inibidores Enzimáticos/farmacologia , Frutosefosfatos/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Glucosiltransferases/isolamento & purificação , Heparina/farmacologia , Isomerases/metabolismo , Manosefosfatos/metabolismo , Metais/farmacologia , Polieletrólitos , Polímeros/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Especificidade por Substrato/efeitos dos fármacos
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