Synthesis Of Isoenzymes Research Articles

Pharmacodynamic gene polymorphism and adverse drug reactionsthen applying antipsychotic drugs

Application of antipsychotic drugs of both the first and subsequent generations quite often causes adverse side effects, which can reduce the compliance to the treatment of patients, reducing their quality of life. One of the most serious NLRs that occur during the period of application of antipsychotic disorders in patients are extrapyramidal disorders (acute dystonia, dyskinesia), malignant neuroleptic syndrome and tardive dyskinesia. During the year of therapy with the use of antipsychotic drugs of the first generation, signs of late dyskinesia appear in 3 to 5% of patients, and in elderly patients this figure is 5 times higher.
 The achievement of recent years in medicine is the application of the pharmacogenetic approach for predicting the patient’s individual response to taking the drug.
 Recent advances in medicine is the practice of pharmacogenetic approach to predict the patient’s individual response to receiving the drug. The pharmacogenetic approach to the prescription of medicines is based on the study of the effect of polymorphism of genes encoding the synthesis of isoenzymes of biotransformation and transport of xenobiotics, as well as the synthesis of elements responsible for the pharmacodynamic component.
 In this article, we will attempt to describe the main adverse side effects arising from the use of antipsychotic drugs, as well as consider pharmacogenetic aspects of their appearance, to summarize the relevant information currently available. arisingfrom the use of antipsychotic drugs, as well as consider pharmacogenetic aspects of their appearance, to summarize the relevant information currently available.

Dual overlapping promoters control napF (periplasmic nitrate reductase) operon expression in Escherichia coli K-12.

Escherichia coli elaborates a flexible respiratory metabolism, involving differential synthesis of isoenzymes for many oxidation and reduction reactions. Periplasmic nitrate reductase, encoded by the napFDAGHBC operon, functions with concentrations of nitrate that are too low to support respiration by membrane-bound nitrate reductase. The napF operon control region exhibits unusual organization of DNA binding sites for the transcription regulators Fnr and NarP, which activate transcription in response to anaerobiosis and nitrate, respectively. Previous studies have shown that the napF operon control region directs synthesis of two transcripts whose 5' ends differ by about 3 nucleotides. We constructed mutant control regions in which either of the two promoter -10 regions is inactivated. Results indicate that the downstream promoter (P1) was responsible for Fnr- and NarP-regulated napF operon expression, whereas transcription from the upstream promoter (P2) was activated only weakly by the Fnr protein and was inhibited by phospho-NarP and -NarL proteins. The physiological function of promoter P2 is unknown. These results establish the unconventional napF operon control region architecture, in which the major promoter P1 is activated by the Fnr protein bound to a site centered at -64.5 with respect to the transcription initiation site, working in conjunction with the phospho-NarP protein bound to a site centered at -44.5.

Rapid Regulation of GAD67 mRNA and Protein Level in Cortical Neurons After Sensory Learning

Cortical representations of different modalities can be modified by sensory learning. Our previous studies in the barrel cortex showed that expansion of the cortical representation of a row of vibrissae could be induced by pairing stimulation of a row of vibrissae with a tail shock. The plastic change in cortical reactivity to the input used during the training was accompanied by increased density of GABA immunoreactive neurons in the involved row of cortical barrels. Using the same paradigm, the present study examined the pathway of GABA synthesis-expression of GAD67 mRNA and immunoreactivity of GAD67 isoenzyme in the barrel cortex of mice after sensory learning. In situ hybridization revealed that the GAD67 mRNA level was elevated in one row of barrels in the trained group as well as in controls receiving vibrissae stimulation alone. In contrast, elevation of immunoreactivity of the GAD67 protein occurred only in the trained group. The density of GABA-immunoreactive neurons in the hollows of barrels representing the row of vibrissae activated during the training was increased by 50%. These data indicated that sensory stimulation alone affected expression of the 67 kDa glutamate decarboxylase isoenzyme synthesis pathway, whereas the processes involved in cortical plasticity induced by associative learning modified this pathway additionally at the level of translation.

Pepsinogen synthesis during long-term culture of porcine chief cells

The purpose of this study was to characterize time-dependent changes in pepsinogen (PG) synthesis of porcine gastric chief cells during long-term monolayer culture. Porcine chief cells were isolated by pronase/collagenase treatment of fundic mucosa and enriched by density gradient and counterflow centrifugation. PG isoenzymes were identified in [ l- 35S]methionine-labelled cultured chief cells by native polyacrylamide gel electrophoresis followed by phosphor imager analysis, protease detection and immunoblots with specific PG A and C antibodies. The obtained results suggest that porcine chief cell cultures, after an initial settling period, reached an approximate steady state in total protein content and synthesis as well as in PG content and isoenzyme pattern from days 3 to 9 of culture. The latter was characterized by the presence of at least two PG A and two PG C isoenzymes. During the supposed steady-state total PG synthesis averaged out at 34±2% of total protein synthesis, as detected by [ l- 35S]methionine incorporation, due to the synthesis of, mainly, PG A2 and, to a much lesser extent, PG C and A1. In line with an active secretion, PG A2 proportion was on average significantly higher in released (44±3%) than in intracellular labelled proteins (19±2%). In addition, PG release from chief cells cultured for 6 and 9 days could be stimulated by cholecystokinin-octapeptide. These data suggest that porcine chief cells in monolayer culture are a model well suited for the quantitative and qualitative characterization of PG isoenzyme synthesis and release during long-term investigations, for which an establishment of a culture steady state appears to be a useful prerequisite.

Heat shock and recovery in aged wheat aleurone layers

AbstractAgeing of wheat seeds (Triticum aestivum cv. Galahad, 1986 harvest) during storage is accompanied by an increase in the proportion of abnormal seedlings produced when aged seed lots germinate. The response of aleurone layers from normally and abnormally germinated seeds to heat shock has been investigated. [14C]-amino acid incorporation into aleurone layers from 3-d normally and abnormally germinated seeds diminished after 4 h at 42°C but the aleurone layers were able to recover significantly during a 5-h period at 20°C following heat shock. [35S]-methionine pulse-labelling of aleurone proteins showed that α-amylase isoenzyme synthesis was abolished upon heat shock in aleurone layers for both normally and abnormally germinated seeds and that only aleurone layers from normally germinated seeds were capable of recommencing substantial α-amylase synthesis during the recovery period. Heat shock caused aleurone layers from abnormally germinated seeds to synthesize polypeptides not synthesized by aleurone layers from normally germinated seeds under the same conditions. The synthesis of certain polypeptides by aleurone layers from abnormally germinated seeds was enhanced at 20°C, 42°C and during recovery compared with normally germinated seeds. These results are discussed in terms of the control of gene expression during heat shock and recovery during seed ageing.

Secretion of pectic isoenzymes by Sclerotinia sclerotiorum

Cultures of Sclerotinia sclerotiorum grown on different pectin-related polysaccharides (citrus pectin, apple pectin, sodium polygalacturonate), carboxymethylcellulose (CMC) or glucose as the only carbon source were examined daily for polygalacturonase and pectinase activities. Electrophoretic forms of polygalacturonase and pectin methylesterase activities were revealed using analytical IEF and sodium polygalacturonate and citrus pectin as substrates in overlay gels. A sequence in the production of pectic enzymes and isoenzyme synthesis was found in pectic-polymer cultures corresponding to the induction of several isoenzymes. Enzyme activities in glucose media were associated with three polygalacturonase and two pectinmethylesterase isoforms which were produced constitutively. Sodium-dodecyl-sulphate polyacrylamide-gel electrophoresis followed by immunoblotting with polyclonal antibodies against an exo-polymethylgalacturonase and an exo-polygalacturonase revealed that these exo-enzymes were secreted from the beginning of cultivation in the different culture media showing characteristics of constitutive enzymes.

Secretion of pectic isoenzymes bySclerotinia sclerotiorum

Cultures of Sclerotinia sclerotiorum grown on different pectin-related polysaccharides (citrus pectin, apple pectin, sodium polygalacturonate), carboxymethylcellulose (CMC) or glucose as the only carbon source were examined daily for polygalacturonase and pectinase activities. Electrophoretic forms of polygalacturonase and pectin methylesterase activities were revealed using analytical IEF and sodium polygalacturonate and citrus pectin as substrates in overlay gels. A sequence in the production of pectic enzymes and isoenzyme synthesis was found in pectic-polymer cultures corresponding to the induction of several isoenzymes. Enzyme activities in glucose media were associated with three polygalacturonase and two pectinmethylesterase isoforms which were produced constitutively. Sodium-dodecyl-sulphate polyacrylamide-gel electrophoresis followed by immunoblotting with polyclonal antibodies against an exo-polymethylgalacturonase and an exo-polygalacturonase revealed that these exo-enzymes were secreted from the beginning of cultivation in the different culture media showing characteristics of constitutive enzymes.

Differential regulation of actin and myosin isoenzyme synthesis in functionally overloaded skeletal muscle

Overload hypertrophy of the chicken anterior latissimus dorsi muscle is accompanied by a replacement of one myosin isoenzyme (slow myosin-1, SM1) by another (slow myosin-2, SM2). To investigate the molecular mechanisms by which these changes occur, we measured the fractional synthesis rates (ks) in vivo of individual myosin-heavy-chain isoenzymes, total actin and total protein during the first 72 h of muscle growth. Although the ks of total protein and actin were doubled at 24 h, the ks for SM1 and SM2 were depressed. However, the ks of both isomyosins were nearly tripled by 72 h. Despite the increase in muscle size observed at 72 h, the amount of SM1 was reduced by half, indicating increased degradation of SM1. Results of translation of polyribosomes in vitro paralleled the results obtained in vivo. The proportion of total polyadenylylated mRNA in total RNA was increased at 48 and 72 h, but unchanged at 24 h despite the increase in protein synthesis at 24 h. Nuclease-protection analyses indicate that the level of specific SM1 and SM2 mRNAs change in a reciprocal fashion during overload. We conclude that gene-specific and temporal differences exist in the regulatory mechanisms that control overload-induced muscle growth.

Proliferative Hairy Cell Leukaemia (HCL-v) Resistant to Alpha-Interferon: Clinical, Diagnostic and In-Vitro Cellular Characteristics

This report details the clinical and cellular features of a patient with 'proliferative' hairy cell leukaemia (HCL-v) who presented with a WBC count of 345 x 10(9)/1. In contrast to typical HCL, there was no significant clinical response to splenectomy or treatment with alpha-interferon but leucophoresis was found to be important in maintaining a stable WBC count. Additionally, morphological (light and electron microscopy), cytochemical (ANAE +, AcP +, TRAcP -) and immunophenotypic (CDlc +, CDllc +, CD19 +, CD20 +, CD23-, CD25-, FMC7 +, HC2-) studies of HCL-v cells were undertaken together with an extensive analysis of cellular characteristics (including RNA/DNA synthesis) following in-vitro culture. In contrast to typical HCL cells, but in common with CLL/PLL cells, TPA did not induce the 'acquisition' of long fibroblast-like cytoplasmic extensions. However, plasmacytoid features could be induced by culture in the presence of TPA plus the calcium ionophore A23187. Furthermore, although some TRAcP isoenzyme synthesis could be induced by TPA, its level of staining (IEF) did not reach the same intensity as that usually observed for HCL. In-vitro culture studies, with TPA and TPA/A23187 as well as a number of immunomodulators, were also used to examine the rates of immunoglobulin (Ig) and beta(2)-microglobulin (B(2)m) secretion. TPA alone was the most potent stimulator of both Ig and B(2)m production whereas the addition of A23187 to TPA cultures induced a marked suppression of Ig production but only minimally affected B(2)m secretion. For comparison, bryostatin-1, r IFN-lambda, r IL-2 and r TNF were all considerably less effective than TPA in the induction of B(2)m production. These observations further support the contention that HCL-v represents a leukaemia subtype intermediate between HCL and B-PLL and that recognition of this variant is of particular importance in therapeutic management.

Induction of drug-metabolizing enzymes in gunn rat liver: Effect of polycyclic aromatic hydrocarbons on cytochrome P-450 regulation

Response of congenitally jaundiced rats (Gunn rats) to administration of polycyclic aromatic hydrocarbons (PAH) was investigated and compared to that of Wistar rats. Unlike Wistar, Gunn males did not exhibit changes in the overall cytochrome P-450 content of hepatic microsomes. The first step in the induction process (i.e. presence of cytosolic receptors for PAH) was found present and functionally similar (number of sites, K d) to that of Wistar rats from which the Gunn strain is derived. An increase in monooxygenase activities related to P-450c and P-450d isoenzymes specifically induced by PAH was noticed, whereas no effect could be detected on the glucuronidation rate of either 4-nitrophenol, testosterone or estrone. As determined by immunoquantification after Western blotting, the iso-enzymatic profile of P-450 from PAH-treated male Gunn rats showed an increase of P-450c and P-450d accompanied by an equivalent decrease in P-4502c (major male-specific isoenzyme). The balance between increase in P-450c and P-450d and decrease in P-4502c may explain the absence of increase in the total P-450 in PAH-treated male Gunn rats. Such a response was not observed in PAH-treated male Wistar rats or in female rats of both strains. In contrast, the response of male Gunn rats to PB treatment was similar to that observed in Wistar rats, i.e. increase in overall cytochrome P-450 content of hepatic microsomes and of specific isoenzyme P-450 b/e. A possible regulation of P-450 isoenzyme synthesis by the intracellular haem pool might be involved.

Synthesis of Isoenzymes of Angiotensin-converting Enzyme in Lung

Synthesis of Isoenzymes of Angiotensin-converting Enzyme in Lung

Synthesis of isoenzymes of angiotensin-converting enzyme in lung

Synthesis of isoenzymes of angiotensin-converting enzyme in lung

Electrophoretic and cytochemical characterization of alpha-naphthyl acetate esterases in acute myeloid leukemia: relationships with membrane receptor and monocyte-specific antigen expression

Alpha-naphthyl acetate esterases (ANAE) were examined by cytochemical and isoelectric focusing (IEF) techniques in 48 cases of acute myeloid leukemia that were classified by conventional morphological criteria. Four main types of ANAE isoenzyme patterns were found by IEF, and comparisons with the expression of membrane receptors (Fc-IgG and C3b) and monocyte-specific antigens (UCHM1, UCHALF, and E11) suggest relationships between ANAE isoenzyme synthesis and distinct myeloid maturational stages. The results further indicate that the blast cells of acute myelomonocytic leukemia (AMML) may represent an immature variant of monocytic leukemia (AMoL) and that morphological examination alone is inadequate in the assessment of monocytic differentiation in acute myeloid leukemias. Inhibition studies of cytochemical ANAE activity with sodium fluoride (NaF) show that the presence of NaF- sensitive or NaF-resistant ANAE enzymes is often unrelated to the diagnostic category of acute leukemia. The results of this study are examined in relation to current concepts of myeloid differentiation, and the application of these findings to the subclassification of acute myeloid leukemias is discussed.

Electrophoretic and Cytochemical Characterization of Alpha-Naphthyl Acetate Esterases in Acute Myeloid Leukemia: Relationships With Membrane Receptor and Monocyte-Specific Antigen Expression

Alpha-naphthyl acetate esterases (ANAE) were examined by cytochemical and isoelectric focusing (IEF) techniques in 48 cases of acute myeloid leukemia that were classified by conventional morphological criteria. Four main types of ANAE isoenzyme patterns were found by IEF, and comparisons with the expression of membrane receptors (Fc-IgG and C3b) and monocyte-specific antigens (UCHM1, UCHALF, and E11) suggest relationships between ANAE isoenzyme synthesis and distinct myeloid maturational stages. The results further indicate that the blast cells of acute myelomonocytic leukemia (AMML) may represent an immature variant of monocytic leukemia (AMoL) and that morphological examination alone is inadequate in the assessment of monocytic differentiation in acute myeloid leukemias. Inhibition studies of cytochemical ANAE activity with sodium fluoride (NaF) show that the presence of NaF-sensitive or NaF-resistant ANAE enzymes is often unrelated to the diagnostic category of acute leukemia. The results of this study are examined in relation to current concepts of myeloid differentiation, and the application of these findings to the subclassification of acute myeloid leukemias is discussed.

α-Amylase Synthesis in Wheat Kernels as Influenced by the Seed Coat

The effect of seed coat removal on the synthesis of alpha-amylase isoenzymes in wheat was investigated. The immature wheat endosperm-aleurone (seed coat and embryo detached) produced considerably less alpha-amylase activity than immature whole or de-embryonated wheat kernels, when incubated under identical conditions of 18.5 C and 99% humidity, in the presence or absence of gibberellic acid (GA(3)). The incubated endosperm-aleurone also exhibited unique alpha-amylase isoenzyme composition when compared to the isoenzyme compositions of incubated whole and de-embryonated immature and mature wheat kernels both in the presence or absence of GA(3). Subsequent studies indicated that the seed coat may contain factor(s) required for normal alpha-amylase isoenzyme synthesis.

Mode of Action of p-Fluorophenylalanine in Aspergillus nidulans: Effect on the Synthesis and Activity of Phosphatase Isoenzymes

The polyacrylamide disc gel electrophoretic pattern of five isoenzymes of phosphomono-esterases (both alkaline and acid) of Aspergillus nidulans has been established. Bands I and V are derepressible acid phosphatases, band II is constitutive acid phosphatase, band III a derepressible alkaline phosphatase and band IV a constitutive alkaline phosphatase. Isoenzyme III can be completely inhibited by p-fluorophenylalanine (FPA). Experiments using FPA, cycloheximide and actinomycin D indicated that transcription for isoenzyme III (inhibited by actinomycin D) took place between 20 and 21 h incubation, and translation of the mRNA so formed occurred between 21 and 22 h. FPA and cycloheximide were both inhibitory at the time of translation. However, cycloheximide caused a gradual reduction in the quantity of all isoenzymes, whereas only isoenzyme III was affected by FPA. The different effect of FPA was confirmed by incorporation of radioactive FPA into isoenzyme III. FPA apparently did not inhibit synthesis of isoenzyme III, but inactivated the isoenzyme III formed in its presence. Constitutive isoenzymes synthesized in the presence of FPA showed normal activity. It is suggested that FPA may not necessarily affect the activity of all proteins synthesized in its presence but whenever it is incorporated into indispensable sites in proteins, it inactivates them. This may be the mechanism of growth inhibition by FPA in Aspergillus nidulans.

Isoenzymes of the Glycolytic and Pentose Phosphate Pathways in Proplastids from the Developing Endosperm of Ricinis communis L.

Two isoenzymes each of hexose-P isomerase, aldolase and 6-P-gluconate dehydrogenase have been found in the endosperm of developing castor beans (Ricinus communis L.). One isoenzyme for each activity is present in the proplastid fraction. Only one form of glucose-6-P dehydrogenase was found. It is suggested that the partition of an enzyme activity between cytosol and plastid is regulated by the synthesis of isoenzymes which are subcellular site specific. In addition, this report describes the use of diethylaminoethyl-Sephadex A-25 sievorptive chromatography for the preparation of plant enzymes.

Amino terminal acetylation and the levels of some erythrocyte proteins

Amino-terminal acetylation of proteins is considered and, in particular, evidence relating to the stage at which acetylation may occur during protein synthesis. The possibility is discussed that the amounts of certain N-acetylated proteins, notably carbonic anhydrases I and II, may be related to the presence of acetylated haemoglobin in human foetal and in adult erythrocytes of certain other species. It is suggested that synchronous synthesis of carbonic anhydrase I and haemoglobin, which occurs mainly at the reticulocyte stage of red cell development, largely accounts for the observed differential effect on the levels of the two isoenzymes in erythrocytes of those species which contain acetylated haemoglobin. Competition for available acetyl groups in reticulocytes, where the main source of such groups, namely mitochondria, begin to disappear, could account for the drastically reduced synthesis of isoenzyme I.

Determination of erythrocyte carbonic anhydrase B and C: an aid in the diagnosis of thyroid disorders?

AbstractTwo genetically distinct forms of erythrocyte carbonic anhydrase, form B and form C, have been assayed by means of electrophoresis on cellulose acetate membranes in 92 euthyroid adults and in 49 patients suffering from thyroid disorders. A negative correlation was found between the concentration of erythrocyte carbonic anhydrase form B and plasma thyroxine. This finding is shown to be due to an effect of the thyroid hormone system on the synthesis of isoenzyme B in the red blood cell precursors. The use of the carbonic anhydrase B assay as a means of measuring the action of the thyroid hormone on the body cells is discussed.

The ontogenetic variformity of lactate dehydrogenase in feline and cavian tissues

1. 1. As an extension of a previous line of research, and in order to provide detailed information on the developmental characteristics of lactate dehydrogenase (EC 1.1.1.27), the properties of this enzyme have been studied over a representative range of intervals during the gestation and post-natal maturation of the cat and guinea pig. 2. 2. These animals occupy significant positions in relation to the available data in other mammalian species, and the results have enabled a number of informative comparisons to be drawn in regard to the morphogenetic processes and the epigenetic control of lactate dehydrogenase biosynthesis in mammals. 3. 3. In particular, the relative ratios of monomer types (A and B) of this enzyme prior to the initiation of funtional differentiation, have been shown to bear a limited phylogenetic inter-relationship. Species within the same sub-order possessed values of a similar magnitude, and a broader correspondence existed between the ratios in related sub-orders. The significance of this phenomenon is discussed in relation to the control of isoenzyme synthesis. 4. 4. Additional information has been provided on the rolel of oxygen and other factors in determining the properties of tissue lactate dehydrogenase in the pre- and post-natal situations.