ChemInform Abstract: AMINO ACIDS AND PEPTIDES. CXXXIV. (1-β-MERCAPTOPROPIONIC ACID, 8-α,Γ-DIAMINOBUTYRIC ACID)VASOPRESSIN AND (1-β-MERCAPTOPROPIONIC ACID, 8-D-ORNITHINE)VASOPRESSIN. SYNTHESIS AND BIOLOGICAL EFFECTS

[1-β-Mercaptopropionic acid, 8-norarginine]vasopressin (L8, D8; I, II) was prepared by condensation of β-benzylthiopropionyl-tyrosyl-phenylalanyl-glutaminyl-asparaginyl-S-benzylcysteine with Nγ-benzyloxycarbonyl-α,γ-diaminobutyryl-glycine amide (L2, D2) by the azide or carbodiimide method, respectively, removal of the benzyloxycarbonyl residue, guanidination of γ-amino groups, removal of protecting groups, closing of the disulfide bridge, and electrophoretic purification. I has an almost 2 times higher antidiuretic effect than DDAVP and a 3 times higher pressor effect than AVP. II has 20-25% of the antidiuretic effect of DDAVP and 16 IU/mg of the pressor effect.

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Vasopressin and oxytocin analogs with interchanged sequence of amino acids in positions 7 and 8. synthesis and biological effects

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19812136 ◽

1981 ◽

Vol 46 (9) ◽

pp. 2136-2139 ◽

Cited By ~ 1

Author(s):

Ivo Bláha ◽

Viktor Krchňák ◽

Milan Zaoral

Keyword(s):

Amino Acids ◽

Solid Phase Synthesis ◽

Solid Phase ◽

Biological Effects ◽

Free Flow ◽

Protecting Groups ◽

Pressor Effect ◽

Phase Synthesis ◽

Antidiuretic Effect

p-Toluenesulfonyl-S-benzylcysteinyl-tyrosyl-phenylalanyl-glutaminyl-asparaginyl-S-benzylcysteinyl-NG-p-toluenesulfanylarginyl-prolyl-glycineamide (I) and S-benzylcysteinyl-tyrosyl-isoleucyl-glutaminyl-asparaginyl-S-benzylcysteinyl-leucyl-prolyl-glycine amide (III) were prepared by solid phase synthesis. After removal of the protecting groups, closure of the disulfide ring, and purification by continuous free-flow electrophoresis [arginine7, proline8]vasopressin (II) and [leucine7, proline8]oxytocin (IV) were obtained. The antidiuretic effect of II is markedly higher than its pressor effect; IV possesses c. 6% of the uterotonic and c. 10% of the galactogogous effect of oxytocin.

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Meroterpenoids: A Comprehensive Update Insight on Structural Diversity and Biology

Biomolecules ◽

10.3390/biom11070957 ◽

2021 ◽

Vol 11 (7) ◽

pp. 957

Author(s):

Mamona Nazir ◽

Muhammad Saleem ◽

Muhammad Imran Tousif ◽

Muhammad Aijaz Anwar ◽

Frank Surup ◽

...

Keyword(s):

Amino Acids ◽

Secondary Metabolites ◽

Biological Effects ◽

Structural Diversity ◽

Chemical Diversity ◽

Biosynthetic Pathways ◽

Natural Sources ◽

Hybrid Compounds ◽

Anti Inflammatory

Meroterpenoids are secondary metabolites formed due to mixed biosynthetic pathways which are produced in part from a terpenoid co-substrate. These mixed biosynthetically hybrid compounds are widely produced by bacteria, algae, plants, and animals. Notably amazing chemical diversity is generated among meroterpenoids via a combination of terpenoid scaffolds with polyketides, alkaloids, phenols, and amino acids. This review deals with the isolation, chemical diversity, and biological effects of 452 new meroterpenoids reported from natural sources from January 2016 to December 2020. Most of the meroterpenoids possess antimicrobial, cytotoxic, antioxidant, anti-inflammatory, antiviral, enzyme inhibitory, and immunosupressive effects.

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F-actin-dependent Translocation of the Rap1 GDP/GTP Exchange Factor RasGRP2

Journal of Biological Chemistry ◽

10.1074/jbc.m313013200 ◽

2004 ◽

Vol 279 (19) ◽

pp. 20435-20446 ◽

Cited By ~ 39

Author(s):

Mariía J. Caloca ◽

José L. Zugaza ◽

Miguel Vicente-Manzanares ◽

Francisco Sánchez-Madrid ◽

Xosé R. Bustelo

Keyword(s):

Signal Transduction ◽

Amino Acids ◽

Subcellular Distribution ◽

Actin Polymerization ◽

Biological Effects ◽

Actin Dynamics ◽

Exchange Factor ◽

Common Structure ◽

Direct Association ◽

P21 Activated Kinase

RasGRPs constitute a new group of diacylglycerol-dependent GDP/GTP exchange factors that activate Ras subfamily GTPases. Despite a common structure, Ras-GRPs diverge in their GTPase specificity, subcellular distribution, and downstream biological effects. The more divergent family member is RasGRP2, a Rap1-specific exchange factor with low affinity toward diacylglycerol. The regulation of RasGRP2 during signal transduction has remained elusive up to now. In this report, we show that the subcellular localization of Ras-GRP2 is highly dependent on actin dynamics. Thus, the induction of F-actin by cytoskeletal regulators such as Vav, Vav2, Dbl, and Rac1 leads to the shift of RasGRP2 from the cytosol to membrane ruffles and its co-localization with F-actin. Treatment of cells with cytoskeletal disrupting drugs abolishes this effect, leading to an abnormal localization of RasGRP2 in cytoplasmic clusters of actin. The use of Rac1 effector mutants indicates that the RasGRP2 translocation is linked exclusively to actin polymerization and is independent of other pathways such as p21-activated kinase JNK, or superoxide production. Biochemical experiments demonstrate that the translocation of RasGRP2 to membrane ruffles is mediated by the direct association of this protein with F-actin, a property contained within its 150 first amino acids. Finally, we show that the RasGRP2/F-actin interaction promotes the regionalized activation of Rap1 in juxtamembrane areas of the cell. These results reveal a novel function of the actin cytoskeleton in mediating the spatial activation of Ras subfamily GTPases through the selective recruitment of GDP/GTP exchange factors.

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