Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.7.7.49 (reverse transcriptase)
31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The antiviral activity of 6-0-butanoylcastanospermine (MDL 28,574) [50% inhibitory concentration (IC50: 1.1 microM)] in JM cells infected with a recent isolate of HIV-1 (GB8), was compared with other inhibitors of glycoprotein-processing enzymes. N-butyldeoxynojirimycin (BuDNJ), deoxynojirimycin (DNJ), castanospermine (CAST) or the reverse transcriptase inhibitor 2'3'-dideoxycytidine (ddC) had activities of 56, 560, 29 and 0.1 microM, respectively. MDL 28,574 was at least 50 times more active than BuDNJ and less active but better tolerated in cell culture than ddC, two compounds currently undergoing clinical trials. The CAST derivative showed good protection in H9 cells infected with HIV-1 (RF; IIIB; U455), and HIV-2 (ROD), although the potency was less than that seen in the JM/GB8 system. HIV-1 glycoproteins, gp160 and gp120, synthesized in H9 cells chronically infected with HIV-1 (RF) and treated with MDL 28,574, were characterized by an increase in relative molecular weight of approximately 7-8000 kD. The ratio of gp120 to gp160 was markedly reduced in treated cells and provided further evidence that cleavage of the gp160 precursor molecule is a major consequence of the inhibition of glycoprotein processing. The intracellular target for MDL 28,574 was verified as alpha-glucosidase-I of the processing enzymes by the analysis of high-glucose glycopeptides recovered from treated mouse cells. This activity correlated with the antiviral effect observed against the growth of a mouse retrovirus, Moloney murine leukemia virus (MOLV), in mouse cells.
...
PMID:6-0-butanoylcastanospermine (MDL 28,574) inhibits glycoprotein processing and the growth of HIVs. 165 79

We have determined the complete nucleotide (nt) sequence of a 2937-bp DNA fragment containing the yeast maltase (EC 3.2.1.20) gene (MAL6S) as well as part of the contiguous maltose permease gene (MAL6T) from the MAL6 locus of Saccharomyces carlsbergensis. The MAL6S gene encodes an alpha-glucosidase that is required for the utilization of maltose as a carbon source by yeast. The 5' transcription initiation sites for both MAL6S and MAL6T were determined by primer extension experiments using reverse transcriptase. The sequence data show one major open reading frame (ORF) of 584 amino acids (aa) for maltase with a calculated Mr of 68 107, somewhat larger than the value of 63 000 previously determined by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) analysis. The nucleotide sequences upstream of both the MAL6S and MAL6T genes, which are divergently transcribed, show common structural features for the transcription initiation of yeast genes as well as signals required for their translation. The codon bias index shows that the MAL6S gene is moderately expressed. The possible significance of two 17-bp dyad symmetric sequences, found in the intergenic region of MAL6S and MAL6T, for the control of expression of these genes is also discussed.
...
PMID:Primary structure of the maltase gene of the MAL6 locus of Saccharomyces carlsbergensis. 351 95

MKC-442, a derivative of the non-nucleoside reverse transcriptase (RT) inhibitor 1-[(2-hydroxyethoxy)methyl)-6-(phenylthio)thymidine (HEPT), showed potent and selective inhibition of human immunodeficiency virus type 1 (HIV-1) replication in vitro, using a range of host-cell/virus systems including human peripheral blood mononuclear cells infected with primary clinical isolates. MKC-442 was evaluated in combination with the nucleoside analogues AZT, ddI and ddC, the non-nucleoside RT inhibitor nevirapine, the HIV-1 proteinase inhibitor Ro-31-8959, and the alpha-glucosidase 1 inhibitor, MDL-28,574, using a cell viability assay. Drug interactions were evaluated by the isobologram technique and by calculating combination indices. Notable synergistic inhibition of HIV-1 replication was observed when MKC-442 was combined with AZT and MDL-28,574 and moderate synergy with ddI. In combination with ddC, nevirapine or Ro-31-8959, only a slightly better than additive effect was observed. Impressive synergy was seen using the three-drug combinations of MKC-442, AZT and MDL-28,574 or MKC-442, AZT and Ro-31-8959. No additional cytotoxicity was observed as measured by [3H]thymidine incorporation by concanavalin A-stimulated peripheral blood mononuclear cells, when MKC-442 was combined with any of the above-mentioned compounds. The use of MKC-442 in a two- or three-drug combination regimen with other RT inhibitors, a proteinase inhibitor or an alpha-glucosidase 1 inhibitor should be considered for HIV-1-related chemotherapy.
...
PMID:The inhibition of human immunodeficiency virus type 1 in vitro by a non-nucleoside reverse transcriptase inhibitor MKC-442, alone and in combination with other anti-HIV compounds. 754 19

An enteric disease of young turkeys, referred to as stunting syndrome (SS), causes reduced growth and impaired feed efficiency. A recently isolated virus, stunting syndrome agent, (SSA) has been found to be the etiologic agent of SS. The objective of the present study was to determine relatedness of the SSA with other viral agents. Serologic (viral neutralization and enzyme-linked immunosorbent assay [ELISA]) assays and a reverse transcriptase-polymerase chain reaction (RT-PCR) were used. The antisera against turkey enteric coronavirus (bluecomb agent), bovine coronavirus (BCV), bovine Breda-1 virus, bovine Breda-2 virus, avian infectious bronchitis virus (IBV), avian influenza virus, Newcastle disease virus (NDV), and transmissible gastroenteritis virus (TGEV) of swine were evaluated by dot-immunobinding avidin-biotin-enhanced ELISA and did not react with SSA. The homologous (anti-SSA) antiserum was positive by ELISA. Similarly, anti-SSA antiserum did not react when NDV, IBV, BCV, or TGEV was used as antigen but did react with the homologous (SSA) virus. The virus neutralization assay was performed by inoculating 24-to-25-day-old turkey embryos via the amniotic route and by assessing the embryo infectivity on the basis of gross intestinal lesions and intestinal maltase activity at 72 hr postinoculation. None of the aforementioned antisera neutralized SSA infectivity in embryos except for the homologous anti-SSA antiserum. A RT-PCR was performed with known primers specific for NDV, IBV, BCV, and TGEV. The known primers failed to amplify SSA genome but amplified their respective viral genomes. We concluded that the SSA was distinct from the viral agents that were evaluated.
...
PMID:Characterization of the stunting syndrome agent: relatedness to known viruses. 1073 43

A variety of milk proteins including lactoferrin, angiogenin-1, alpha-lactalbumin, beta-lactoglobulin, lactoperoxidase, casein and the novel whey proteins lactogenin and glycolactin were tested for inhibitory activity toward human immunodeficiency virus-1 reverse transcriptase (HIV-1 RT), alpha-glucosidase, beta-glucosidase and beta-glucuronidase. Lactoferrin exerted the most potent inhibitory action with an IC50 of about 6 microM. Lactoperoxidase, lactogenin, angiogenin-1 and glycolactin inhibited HIV-1 RT activity with decreasing potencies. Beta-lactoglobulin, alpha-lactalbumin and casein displayed little or no inhibitory effect. Succinylation with succinic anhydride augmented the inhibitory effect of glycolactin, beta-lactoglobulin, alpha-lactalbumin, casein and human lactoferrin. The inhibitory effect of the various milk proteins on the activities of alpha-glucosidase, beta-glucosidase and beta-glucuronidase was meager. Succinylation tended to increase the alpha-glucosidase-inhibitory effect of milk proteins but neither their beta-glucosidase-inhibitory nor beta-glucuronidase-inhibitory effect was affected.
...
PMID:First demonstration of an inhibitory activity of milk proteins against human immunodeficiency virus-1 reverse transcriptase and the effect of succinylation. 1110 90

Evidence is presented for the existence of multiple proteins with antifungal and antiviral potency in cowpea seeds. The two proteins, designated alpha- and beta-antifungal proteins in accordance with their order of elution from the CM-Sepharose column, were capable of inhibiting human immunodeficiency virus (HIV) reverse transcriptase and one of the glycohydrolases associated with HIV infection, alpha-glucosidase, but beta-glucuronidase was not repressed. The ability of the proteins in retarding mycelial growth of a variety of fungi was also demonstrated with alpha-antifungal protein being more potent in most of the cases. Beta-antifungal protein was more active in only one instance. Both antifungal proteins had low cell-free translation-inhibitory activity. The proteins were adsorbed on Affi-gel blue gel-and CM-Sepharose but could be separated from one another during chromatography on the latter medium by means of a linear NaCl concentration gradient. Different molecular weights were exhibited by the proteins, being 28 kDa and 12 kDa respectively for alpha- and beta- antifungal proteins. Alpha-antifungal protein was characterized by an N-terminal sequence showing close resemblance to sequences of chitinases. Beta-antifungal protein exhibited an N-terminal sequence hitherto unknown in the literature.
...
PMID:Structurally dissimilar proteins with antiviral and antifungal potency from cowpea (Vigna unguiculata) seeds. 1119 27

A protein designated hypogin, with a prominent suppressive action on the growth of the fungi Mycosphaerella arachidicola, Fusarium oxysporum and Coprinus comatus, was isolated from seeds of the peanut Arachis hypogaea. The protein inhibited human immunodeficiency virus (HIV) reverse transcriptase and enzymes associated with HIV infection including alpha-glucosidase and beta-glucosidase. The proliferative response of mouse splenocytes was attenuated in the presence of the protein. The protein exhibited a molecular mass of 7.2 kDa in tricine gel electrophoresis and gel filtration on Superdex 75 and an N-terminal sequence resembling peanut allergen Ara H1. The isolation procedure involved affinity chromatography on Affi-gel blue gel and ion-exchange chromatography on CM-Sepharose. The protein was adsorbed in both chromatographic media.
...
PMID:Hypogin, a novel antifungal peptide from peanuts with sequence similarity to peanut allergen. 1132 90

From the roots of the Chinese medicinal herb Pseudostellaria heterophylla a single-chained lectin with a molecular weight of 36 kDa and high hemagglutinating activity was isolated. The lectin was adsorbed on DEAE-cellulose in 10 mM Tris-HCI buffer (pH 7.4) and was eluted by the same buffer containing 50 mM NaCl. It was adsorbed on SP-Sepharose in 10mM NH4OAc (pH 4.5) and eluted by approximately 0.5 M NaCl in the same buffer. The hemagglutinating activity of the lectin could not be inhibited by a large variety of monosaccharides, but was largely abrogated by exposure to 0.05 M HCl, 0.05M NaOH or 80 degrees C. However, about 50% of the activity remained after exposure to 0.025M NaOH or 40 degrees C. Despite possession of an N-terminal sequence exhibiting some similarity to thaumatin-like proteins with antifungal activity, the lectin was devoid of antifungal activity. The lectin exerted some inhibitory effect on the glycohydrolases alpha-glucosidase, beta-glucosidase and beta-glucuronidase which are involved in HIV infection but had no suppressive action on human immunodeficiency virus-type 1 reverse transcriptase.
...
PMID:A novel lectin from Pseudostellaria heterophylla roots with sequence simularity to Kunitz-type soybean trypsin inhibitor. 1144 23

A variety of lectins were tested in vitro for inhibitory action against the activities of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase and the N-glycohydrolases (alpha-glucosidase, beta-glucosidase and beta-glucuronidase). Lectins from Phaseolus vulgaris, Momordica charantia, Ricinus communis and its constituent chains, and Agaricus bisporus were able to inhibit HIV-1 reverse transcriptase. P. vulgaris lectin and A. bisporus lectin were the most potent. The aforementioned lectins had only weak or no inhibitory effects on the glycohydrolases. The inhibitory effect of polysaccharopeptide from the mushroom Coriolus versicolor on HIV-1 reverse transcriptase and alpha-glucosidase was enhanced after chemical modification with chlorosulfonic acid. However, the inhibitory effect of the algal polysaccharide fucoidan on HIV-1 reverse transcriptase and alpha-glucosidase was not augmented by sulfation. Trypsin inhibitors from Phaseolus lunatus and Glycine max, gossypol and alkaloids from Corydalis yanhusuo were able to inhibit HIV-1 reverse transcriptase. Dicoumarol was capable of inhibiting HIV-1 reverse transcriptase, alpha-glucosidase, beta-glucosidase and beta-glucuronidase.
...
PMID:Examination of lectins, polysaccharopeptide, polysaccharide, alkaloid, coumarin and trypsin inhibitors for inhibitory activity against human immunodeficiency virus reverse transcriptase and glycohydrolases. 1158 48

A homodimeric lectin adsorbed on Affi-gel blue gel and CM-Sepharose and possessing a molecular weight of 67 kDa was isolated from red kidney beans. The hemagglutinating activity of this lectin was inhibited by glycoproteins but not by simple sugars. The lectin manifested inhibitory activity on human immunodeficiency virus-1 reverse transcriptase and alpha-glucosidase. The N-terminal sequence of the lectin exhibited some differences from previously reported lectins from Phaseolus vulgaris but showed some similarity to chitinases. It exerted a suppressive effect on growth of the fungal species Fusarium oxysporum, Coprinus comatus, and Rhizoctonia solani. The lectin had low ribonuclease and negligible translation-inhibitory activities.
...
PMID:Isolation of a homodimeric lectin with antifungal and antiviral activities from red kidney bean (Phaseolus vulgaris) seeds. 1173 88


1 2 Next >>

---