EFFECT OF OXIDATION ON BIOLOGICAL AND IMMUNOLOGICAL ACTIVITY OF PORCINE PARATHYROID HORMONE

1974 ◽  
Vol 63 (1) ◽  
pp. 117-124 ◽  
Author(s):  
J. L. H. O'RIORDAN ◽  
J. S. WOODHEAD ◽  
G. N. HENDY ◽  
J. A. PARSONS ◽  
C. J. ROBINSON ◽  
...  
Keyword(s):  
Biological Activity ◽  
Parathyroid Hormone ◽  
Cysteine Oxidation ◽  
Subsequent Reduction ◽  
Immunological Activity ◽  
Parathyroid Hormones ◽  
Methionine Residue

SUMMARY The presence of a single methionine in porcine parathyroid hormone, at position 8, permitted assessment of the role of this residue separate from the second methionine residue found at position 18 of bovine and human parathyroid hormones. Oxidation of the solitary methionine of porcine parathyroid hormone to the sulphoxide destroyed biological activity, but this was restored by subsequent reduction with cysteine. Oxidation of the hormone did not, however, affect its immunological activity; therefore, oxidation of the hormone may bring about dissociation of biological and immunological activity.

EFFECT OF CYSTEINE ON THE BIOLOGICAL AND IMMUNOLOGICAL ACTIVITY OF HUMAN AND BOVINE PARATHYROID HORMONE

1973 ◽  
Vol 58 (1) ◽  
pp. 1-10 ◽  
Author(s):  
JOAN M. ZANELLI ◽  
D. ATKINS ◽  
M. PEACOCK
Keyword(s):  
Hydrogen Peroxide ◽  
Biological Activity ◽  
Parathyroid Hormone ◽  
Amino Acid ◽  
Response Curve ◽  
Calcium Release ◽  
Human Parathyroid Hormone ◽  
Immunological Activity ◽  
Cysteine Hydrochloride ◽  
Bovine Parathyroid Hormone

SUMMARY Human parathyroid hormone extracted from adenomata was assayed biologically by the release of calcium from mouse calvaria in organ culture and immunologically by immunoassay. The human hormone gave a logdose-response curve for calcium release and assayed at 12 units/mg in terms of the M.R.C. Bovine Research Standard A. Reduction with hot cysteine hydrochloride increased the biological activity of human hormone threefold, and the bovine hormone 4½-fold. An increase in immunological activity could only be shown with bovine hormone, and the purer the preparation the less was the activation of both biological and immunological potencies. Oxidation with hydrogen peroxide destroyed the biological activity of the bovine hormone but some residual immunological activity of the bovine and human hormones could always be detected. Back reduction with hot cysteine hydrochloride restored the biological and immunological activities of the bovine hormone and the immunological activity of the human hormone but never to the levels of the untreated hormones. It is suggested that these changes in potency can be induced by changes in the chemistry of the molecule rather than in its metabolism and that the immunological differences between bovine and human hormone represent minor differences in the amino acid sequence of these two hormones.

CHEMISTRY OF GONADOTROPHINS IN RELATION TO THEIR ANTIGENIC PROPERTIES

1969 ◽  
Vol 62 (1_Suppl) ◽  
pp. S13-S30 ◽  
Author(s):  
W. R. Butt
Keyword(s):  
Biological Activity ◽  
Guinea Pigs ◽  
Complement Fixation ◽  
Neuraminic Acid ◽  
Fixation Technique ◽  
Immunological Activity ◽  
Antigenic Properties ◽  
Specific Antisera ◽  
Structural Differences

ABSTRACT Several chemical differences between FSH, LH and HCG have been reported: thus LH and HCG are richer in proline than FSH and FSH and HCG contain more N-acetyl neuraminic acid than LH. Sub-units of LH are formed by treatment with urea, guanidine or acid. HCG also may contain two sub-units. The sub-units from LH are biologically inert but retain their immunological activity: biological activity is restored when the sub-units are incubated together. There is much evidence from chemical and enzymic reactions that antigenic groups are distinct from those parts of the molecule essential for biological activity. N-acetyl neuraminic acid and probably other carbohydrates in FSH and HCG are not involved in immunological activity but are necessary for biological activity. Histidine, methionine and possibly cysteine appear to be essential for biological but not immunological activity of FSH, while tryptophan and possibly tyrosine are not essential for either. A few highly specific antisera to gonadotrophins have been prepared in rabbits and guinea pigs to crude antigens: there is no evidence that purified antigens are more likely to produce specific antisera. Differences in the immunological reactivities of urinary compared with pituitary gonadotrophins have been observed both by radioimmunoassay and by the complement fixation technique. The latter may be particularly useful for detecting structural differences in the hormones.

Biological activity of novel thyroid hormone analogues: role of Na+ taurocholate cotransporting polypeptide in liver selectivity

2015 ◽  
Author(s):  
Giulia Brigante ◽  
Bo Carlsson ◽  
Simone Kersseboom ◽  
Robin P Peeters ◽  
Theo J Visser
Keyword(s):  
Biological Activity ◽  
Thyroid Hormone

scholarly journals Studies on the Role of Methylated Bases in the Biological Activity of Soluble Ribonucleic Acid

1964 ◽  
Vol 239 (9) ◽  
pp. 2918-2926
Author(s):  
Alan Peterkofsky ◽  
Celia Jesensky ◽  
Arthur Bank ◽  
Alan H. Mehler
Keyword(s):  
Biological Activity ◽  
Ribonucleic Acid

scholarly journals Transcriptome Reveals Roles of Lignin-Modifying Enzymes and Abscisic Acid in the Symbiosis of Mycena and Gastrodia elata

2021 ◽  
Vol 22 (12) ◽  
pp. 6557
Author(s):  
Li-Ying Ren ◽  
Heng Zhao ◽  
Xiao-Ling Liu ◽  
Tong-Kai Zong ◽  
Min Qiao ◽  
...  
Keyword(s):  
Biological Activity ◽  
Abscisic Acid ◽  
Lignin Degradation ◽  
Molecular Mechanisms ◽  
Receptor Protein ◽  
Gastrodia Elata ◽  
Upregulated Genes ◽  
Aba Biosynthesis ◽  
Seed Coats

Gastrodia elata is a well-known medicinal and heterotrophic orchid. Its germination, limited by the impermeability of seed coat lignin and inhibition by abscisic acid (ABA), is triggered by symbiosis with fungi such as Mycena spp. However, the molecular mechanisms of lignin degradation by Mycena and ABA biosynthesis and signaling in G. elata remain unclear. In order to gain insights into these two processes, this study analyzed the transcriptomes of these organisms during their dynamic symbiosis. Among the 25 lignin-modifying enzyme genes in Mycena, two ligninolytic class II peroxidases and two laccases were significantly upregulated, most likely enabling Mycena hyphae to break through the lignin seed coats of G. elata. Genes related to reduced virulence and loss of pathogenicity in Mycena accounted for more than half of annotated genes, presumably contributing to symbiosis. After coculture, upregulated genes outnumbered downregulated genes in G. elata seeds, suggesting slightly increased biological activity, while Mycena hyphae had fewer upregulated than downregulated genes, indicating decreased biological activity. ABA biosynthesis in G. elata was reduced by the downregulated expression of 9-cis-epoxycarotenoid dioxygenase (NCED-2), and ABA signaling was blocked by the downregulated expression of a receptor protein (PYL12-like). This is the first report to describe the role of NCED-2 and PYL12-like in breaking G. elata seed dormancy by reducing the synthesis and blocking the signaling of the germination inhibitor ABA. This study provides a theoretical basis for screening germination fungi to identify effective symbionts and for reducing ABA inhibition of G. elata seed germination.

scholarly journals Differential Role of Threonine and Tyrosine Phosphorylation in the Activation and Activity of the Yeast MAPK Slt2

2021 ◽  
Vol 22 (3) ◽  
pp. 1110
Author(s):  
Gema González-Rubio ◽  
Ángela Sellers-Moya ◽  
Humberto Martín ◽  
María Molina
Keyword(s):  
Cell Wall ◽  
Biological Activity ◽  
Biological Significance ◽  
Mitogen Activated Protein Kinase ◽  
Activation Loop ◽  
High Increase ◽  
Dual Specificity ◽  
Mitogen Activated Protein ◽  
Full Activation

The Mitogen-Activated Protein Kinase (MAPK) Slt2 is central to signaling through the yeast Cell Wall Integrity (CWI) pathway. MAPKs are regulated by phosphorylation at both the threonine and tyrosine of the conserved TXY motif within the activation loop (T190/Y192 in Slt2). Since phosphorylation at both sites results in the full activation of MAPKs, signaling through MAPK pathways is monitored with antibodies that detect dually phosphorylated forms. However, most of these antibodies also recognize monophosphorylated species, whose relative abundance and functionality are diverse. By using different phosphospecific antibodies and phosphate-affinity (Phos-tag) analysis on distinct Slt2 mutants, we determined that Y192- and T190-monophosphorylated species coexist with biphosphorylated Slt2, although most of the Slt2 pool remains unphosphorylated following stress. Among the monophosphorylated forms, only T190 exhibited biological activity. Upon stimulation, Slt2 is first phosphorylated at Y192, mainly by the MAPKK Mkk1, and this phosphorylation is important for the subsequent T190 phosphorylation. Similarly, dephosphorylation of Slt2 by the Dual Specificity Phosphatase (DSP) Msg5 is ordered, with dephosphorylation of T190 depending on previous Y192 dephosphorylation. Whereas Y192 phosphorylation enhances the Slt2 catalytic activity, T190 is essential for this activity. The conserved T195 residue is also critical for Slt2 functionality. Mutations that abolish the activity of Slt2 result in a high increase in inactive Y192-monophosphorylated Slt2. The coexistence of different Slt2 phosphoforms with diverse biological significance highlights the importance of the precise detection of the Slt2 phosphorylation status.

scholarly journals Role of peptide backbone conformation on biological activity of chemotactic peptides.

1991 ◽  
Vol 266 (28) ◽  
pp. 18460-18468
Author(s):  
A.R. Dentino ◽  
P.A. Raj ◽  
K.K. Bhandary ◽  
M.E. Wilson ◽  
M.J. Levine
Keyword(s):  
Biological Activity ◽  
Peptide Backbone ◽  
Backbone Conformation ◽  
Chemotactic Peptides ◽  
Peptide Backbone Conformation

scholarly journals Role of parathyroid hormone in the glucose intolerance of chronic renal failure.

1985 ◽  
Vol 75 (3) ◽  
pp. 1037-1044 ◽  
Author(s):  
M Akmal ◽  
S G Massry ◽  
D A Goldstein ◽  
P Fanti ◽  
A Weisz ◽  
...  
Keyword(s):  
Renal Failure ◽  
Parathyroid Hormone ◽  
Chronic Renal Failure ◽  
Glucose Intolerance

The biological activity of glucagon–phospholipid complexes

1983 ◽  
Vol 61 (7) ◽  
pp. 688-691 ◽  
Author(s):  
J. J. Liepnieks ◽  
P. Stoskopf ◽  
E. A. Carrey ◽  
C. Prosser ◽  
R. M. Epand
Keyword(s):  
Biological Activity ◽  
Adenylate Cyclase ◽  
Plasma Membranes ◽  
Bovine Brain ◽  
Water Soluble ◽  
Dipalmitoyl Phosphatidylcholine ◽  
Dimyristoyl Phosphatidylcholine ◽  
Lipoprotein Complex ◽  
Stimulation Of

Glucagon can form water-soluble complexes with phospholipids. The incorporation of glucagon into these lipoprotein particles reduces the biological activity of the hormone. The effect is observed only at temperatures below the phase transition temperature of the phospholipid and results in a decreased stimulation of the adenylate cyclase of rat liver plasma membranes by the lipoprotein complex as compared with the hormone in free solution. Two- to five-fold higher concentrations of glucagon are required for half-maximal stimulation of adenylate cyclase when the hormone is complexed with dimyristoyl phosphatidylcholine, dipalmitoyl phosphatidylcholine, or bovine brain sphingomyelin. A possible role of lipoprotein-associated hormones in the development of insulin resistance is discussed.

scholarly journals Az ösztrogénmetabolom biológiai és klinikai jelentősége lokális folyamatokban

2017 ◽  
Vol 158 (24) ◽  
pp. 929-937
Author(s):  
Krisztián Kovács ◽  
Barna Vásárhelyi ◽  
Katalin Mészáros ◽  
Attila Patócs ◽  
Gellért Karvaly
Keyword(s):  
Biological Activity ◽  
Clinical Significance ◽  
Physiological Role ◽  
Tissue Homeostasis ◽  
Diagnostic Significance ◽  
Peripheral Tissues ◽  
Breakdown Process ◽  
Specific Manner ◽  
Related Compounds

Abstract: Considerable knowledge has been gathered on the physiological role of estrogens. However, fairly little information is available on the role of compounds produced in the breakdown process of estrone and estradiol wich may play a role in various diseases associated with estrogen impact. To date, approximately 15 extragonadal estrogen-related compounds have been identified. These metabolites may exert protective, or, instead, pro-inflammatory and/or pro-oncogenic activity in a tissue-specific manner. Systemic and local estrogen metabolite levels are not necesserily correlated, which may promote the diagnostic significance of the locally produced estrogen metabolites in the future. The aim of the present study is a bibliographic review of the extragonadal metabolome in peripheral tissues, and to highlight the role of the peripheral tissue homeostasis of estrogens as well as the non-hormonal biological activity and clinical significance of the estrogen metabolome. Orv Hetil. 2017; 158(24): 929–937.

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