Immunization of merino ewes with a synthetic inhibin peptide or with preparations obtained from bovine and porcine follicular fluids by immunoaffinity chromatography result in different effects on ovulation rate and on plasma gonadotrophin concentrations

1991 ◽  
Vol 3 (6) ◽  
pp. 659 ◽  
Author(s):  
T O'Shea ◽  
CM Andrews ◽  
BM Bindon ◽  
MA Hillard ◽  
K Miyamoto ◽  
...  

Ewes were immunized with either a synthetic peptide (peptide 1-32) that has an amino acid sequence identity with the first 32 amino acids at the amino terminal of the alpha-subunit of porcine inhibin, or with bovine or porcine monoclonal antibody purified inhibin (bMPI and pMPI respectively), obtained by immunochromatography from follicular fluids. The peptide 1-32 was conjugated to albumin before use. Peptide 1-32 and bMPI increased ovulation rate and number of follicles (greater than or equal to 5 mm diameter). Although bMPI increased plasma FSH concentration the peptide did not. pMPI had no effect on ovarian activity but markedly elevated both plasma FSH and LH concentrations. The plasma LH concentration was lowered in ewes immunized with peptide 1-32. It appears, therefore, that ovulation rate can be increased following increased plasma FSH concentrations at luteolysis or in the absence of such an increase. Conversely, greatly increased plasma gonadotrophin concentrations at luteolysis (pMPI) were not followed by an increase in ovulation rate. Antibodies in the plasma of ewes immunized with peptide 1-32 and bMPI bound to iodinated synthetic human inhibin alpha-chain 6-30 peptide. The results suggest that ovulation rate is at least partly determined by intraovarian factors.

1993 ◽  
Vol 69 (03) ◽  
pp. 240-246 ◽  
Author(s):  
Midori Shima ◽  
Dorothea Scandella ◽  
Akira Yoshioka ◽  
Hiroaki Nakai ◽  
Ichiro Tanaka ◽  
...  

SummaryA neutralizing monoclonal antibody, NMC-VIII/5, recognizing the 72 kDa thrombin-proteolytic fragment of factor VIII light chain was obtained. Binding of the antibody to immobilized factor VIII (FVIII) was completely blocked by a light chain-specific human alloantibody, TK, which inhibits FVIII activity. Immunoblotting analysis with a panel of recombinant protein fragments of the C2 domain deleted from the amino-terminal or the carboxy-terminal ends demonstrated binding of NMC-VIII/5 to an epitope located between amino acid residues 2170 and 2327. On the other hand, the epitope of the inhibitor alloantibody, TK, was localized to 64 amino acid residues from 2248 to 2312 using the same recombinant fragments. NMC-VIII/5 and TK inhibited FVIII binding to immobilized von Willebrand factor (vWF). The IC50 of NMC-VIII/5 for the inhibition of binding to vWF was 0.23 μg/ml for IgG and 0.2 μg/ml for F(ab)'2. This concentration was 100-fold lower than that of a monoclonal antibody NMC-VIII/10 which recognizes the amino acid residues 1675 to 1684 within the amino-terminal portion of the light chain. The IC50 of TK was 11 μg/ml by IgG and 6.3 μg/ml by F(ab)'2. Furthermore, NMC-VIII/5 and TK also inhibited FVIII binding to immobilized phosphatidylserine. The IC50 for inhibition of phospholipid binding of NMC-VIII/5 and TK (anti-FVIII inhibitor titer of 300 Bethesda units/mg of IgG) was 10 μg/ml.


Biologia ◽  
2011 ◽  
Vol 66 (1) ◽  
Author(s):  
Dessy Natalia ◽  
Keni Vidilaseris ◽  
Pasjan Satrimafitrah ◽  
Wangsa Ismaya ◽  
Purkan ◽  
...  

AbstractGlucoamylase from the yeast Saccharomycopsis fibuligera R64 (GLL1) has successfully been purified and characterized. The molecular mass of the enzyme was 56,583 Da as determined by mass spectrometry. The purified enzyme demonstrated optimum activity in the pH range of 5.6–6.4 and at 50°C. The activity of the enzyme was inhibited by acarbose with the IC50 value of 5 μM. GLL1 shares high amino acid sequence identity with GLU1 and GLA1, which are Saccharomycopsis fibuligera glucoamylases from the strains HUT7212 and KZ, respectively. The properties of GLL1, however, resemble that of GLU1. The elucidation of the primary structure of GLL1 contributes to the explanation of this finding.


Plant Disease ◽  
2000 ◽  
Vol 84 (7) ◽  
pp. 739-742 ◽  
Author(s):  
M. A. V. Alexandre ◽  
L. M. L. Duarte ◽  
E. B. Rivas ◽  
C. M. Chagas ◽  
M. M. Barradas ◽  
...  

Petunia plants from a nursery in the State of Rio Grande do Sul, Brazil, showed pronounced vein banding and contained isometric particles with diameters of approximately 45 and 30 nm. The larger ones apparently represent a caulimovirus, while the smaller ones, which included both empty shells and full particles, were identified as those of a new tymovirus for which we propose the name Petunia vein banding virus (PetVBV). Originally, PetVBV was transmitted only with difficulty to healthy petunia plants. However, from an experimentally infected petu-nia, it was later readily transmitted also to Nicotiana benthamiana and Nicandra physalodes, but not to other species in the Solanaceae or other plant families. It produces cytopathic effects typical for tymovirus infections. Its coat protein shows approximately 65% amino acid sequence identity with those of Eggplant mosaic and Andean potato latent viruses, to which it is also serologically more closely related than to any other tymoviruses.


1996 ◽  
Vol 1996 ◽  
pp. 145-145
Author(s):  
V L Glasgow ◽  
A H Stewart ◽  
S A Edwards

In commercial systems it is highly desirable that gilts are synchronised into a predictable first heat. The use of PMSG/hCG injections (PG 600) has met with some success inducing a synchronised fertile oestrus and slightly increased ovulation rate (Schilling and Cerne, 1972) in gilts and anoestrus sows. Diets containing a high proportion of dietary fibre may influence litter size in gilts (Stewart et al, 1995). The aim of this study was to determine the effect of a high level of dietary fibre on oestrus expression and ovulation rate of gilts synchronised with exogenous gonadotrophins (PG600) or given daily boar stimulus.


1990 ◽  
Vol 111 (4) ◽  
pp. 1427-1435 ◽  
Author(s):  
Y Audigier ◽  
L Journot ◽  
C Pantaloni ◽  
J Bockaert

GTP-binding proteins which participate in signal transduction share a common heterotrimeric structure of the alpha beta gamma-type. In the activated state, the alpha subunit dissociates from the beta gamma complex but remains anchored in the membrane. The alpha subunits of several GTP-binding proteins, such as Go and Gi, are myristoylated at the amino terminus (Buss, J. E., S. M. Mumby, P. J. Casey, A. G. Gilman, and B. M. Sefton. 1987. Proc. Natl. Acad. Sci. USA. 84:7493-7497). This hydrophobic modification is crucial for their membrane attachment. The absence of fatty acid on the alpha subunit of Gs (Gs alpha), the protein involved in adenylate cyclase activation, suggests a different mode of anchorage. To characterize the anchoring domain of Gs alpha, we used a reconstitution model in which posttranslational addition of in vitro-translated Gs alpha to cyc- membranes (obtained from a mutant of S49 cell line which does not express Gs alpha) restores the coupling between the beta-adrenergic receptor and adenylate cyclase. The consequence of deletions generated by proteolytic removal of amino acid sequences or introduced by genetic removal of coding sequences was determined by analyzing membrane association of the proteolyzed or mutated alpha chains. Proteolytic removal of a 9-kD amino-terminal domain or genetic deletion of 28 amino-terminal amino acids did not modify the anchorage of Gs alpha whereas proteolytic removal of a 1-kD carboxyterminal domain abolished membrane interaction. Thus, in contrast to the myristoylated alpha subunits which are tethered through their amino terminus, the carboxy-terminal residues of Gs alpha are required for association of this protein with the membrane.


1987 ◽  
Vol 104 (5) ◽  
pp. 1239-1248 ◽  
Author(s):  
E S Sztul ◽  
D Biemesderfer ◽  
M J Caplan ◽  
M Kashgarian ◽  
J L Boyer

Controversy has recently developed over the surface distribution of Na+,K+-ATPase in hepatic parenchymal cells. We have reexamined this issue using several independent techniques. A monoclonal antibody specific for the endodomain of alpha-subunit was used to examine Na+,K+-ATPase distribution at the light and electron microscope levels. When cryostat sections of rat liver were incubated with the monoclonal antibody, followed by either rhodamine or horseradish peroxidase-conjugated goat anti-mouse secondary, fluorescent staining or horseradish peroxidase reaction product was observed at the basolateral surfaces of hepatocytes from the space of Disse to the tight junctions bordering bile canaliculi. No labeling of the canalicular plasma membrane was detected. In contrast, when hepatocytes were dissociated by collagenase digestion, Na+,K+-ATPase alpha-subunit was localized to the entire plasma membrane. Na+,K+-ATPase was quantitated in isolated rat liver plasma membrane fractions by Western blots using a polyclonal antibody against Na+,K+-ATPase alpha-subunit. Plasma membranes from the basolateral domain of hepatocytes possessed essentially all of the cell's estimated Na+,K+-ATPase catalytic activity and contained a 96-kD alpha-subunit band. Canalicular plasma membrane fractions, defined by their enrichment in alkaline phosphatase, 5' nucleotidase, gamma-glutamyl transferase, and leucine aminopeptidase had no detectable Na+,K+-ATPase activity and no alpha-subunit band could be detected in Western blots of these fractions. We conclude that Na+,K+-ATPase is limited to the sinusoidal and lateral domains of hepatocyte plasma membrane in intact liver. This basolateral distribution is consistent with its topology in other ion-transporting epithelia.


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