Hepatic silver binding protein (Ag BP) from sparrow (Passer domesticus)

A silver binding protein (Ag BP) has been identified in the liver of sparrows administered a tracer dose of 110mAg. The protein as purified by gel-filtration shows a major absorption maximum at 260 nm and a minor one at 225 nm. It has a mol.wt of 9500 daltons and is stable when exposed to high temperature (64 degrees C for 15 min) as well as to acidic pH (2.2).     

Hepatic silver binding protein (Ag BP) from sparrow (Passer domesticus)

Summary A silver binding protein (Ag BP) has been identified in the liver ofsparrows administered a tracer dose of^110mAg. The protein as purified by gel-filtration shows a major absorption maximum at 260 nm and a minor one at 225 nm. It has a mol.wt of 9500 daltons and is stable when exposed to high temperature (64°C for 15 min) as well as to acidic pH (2.2).     

N-cadherin detected in the membrane fraction of lens fiber cells

N-cadherin was identified as a glycoprotein present in the fiber cell membranes of frog, chick, bovine, rabbit and human lenses. The molecular size of N-cadherin varies with the species. Homogenization of the chick lens in the presence of Ca2+ resulted in a decrease in the concentration of N-cadherin. This suggests that the lens contains a Ca2(+)-activated protease which can act on N-cadherin.     

Hemisphaericin-D, a dialysable and polymerizable protease found in Bromelia hemisphaerica.

Proteolytic activity was detected outside dialysis bag filled with Bromelia hemisphaerica fruit juice. The dialysable protease was concentrated and purified from small molecular weight contaminants on Sephadex G-10 columns. Acrylamide gel electrophoresis of the dialysable protease, in the presence of SDS and 2-mercaptoethanol, demonstrated a single protein band of about 8000 daltons mol. wt. The same single band with identical mobility was shown with Hemisphaericin, the enzyme retained inside the dialysis bag. The small protease, named Hemisphaericin-D was antigenic in rabbits and the antibodies cross-reacted fully with Hemisphaericin. Hemisphaericin-D appears not to be a degradation product of Hemisphaericin.     

N-cadherin detected in the membrane fraction of lens fiber cells

Summary N-cadherin was identified as a glycoprotein present in the fiber cell membranes of frog, chick, bovine, rabbit and human lenses. The molecular size of N-cadherin varies with the species. Homogenization of the chick lens in the presence of Ca²⁺ resulted in a decrease in the concentration of N-cadherin. This suggests that the lens contains a Ca²⁺-activated protease which can act on N-cadherin.     

Molecular cloning of the fibroin light chain complementary DNA and its use in the study of the expression of the light chain gene in the posterior silk gland of Bombyx mori

Fibroin light chain (L-chain) mRNA (mol. wt 4.0 X 10(5) daltons) was purified from the posterior silk gland of the silkworm, Bombyx mori (J-131 strain). Double-stranded complementary DNA was synthesized and inserted into the PstI site of pBR322 employing the oligo(dC)-oligo(dG) tailing method. Several recombinant plasmids containing the inserts of about 800 base pairs were isolated. Hybridization-translation assay demonstrated that these clones hybridized specifically with the fibroin L-chain mRNA. One of these clones (pLA23) was used as a probe to investigate relative concentrations of the fibroin L-chain gene and mRNA in the posterior silk glands at different stages of late larval development.     

Hemisphaericin-D,a dialysable and polymerizable protease found in Bromelia hemisphaerica

Summary Proteolytic activity was detected outside dialysis bag filled with Bromelia hemisphaerica fruit juice. The dialysable protease was concentrated and purified from small molecular weight contaminants on Sephadex G-10 columns. Acrylamide gel electrophoresis of the dialysable protease, in the presence of SDS and 2-mercaptoethanol. demonstrated a single protein band of about 8000 daltons mol. wt. The same single band with identical mobility was shown with hemisphaericin, the enzyme retained inside the dialysis bag. The small protease, named Hemisphaericin-D was antigenic in rabbits and the antibodies cross-reacted fully with Hemisphaericin. Hemisphaericin-D appears not to be a degradation product of Hemisphaericin.This is contribution No. 22 from Departamento de Biología Experimental, Facultad de Medicina, UNAM, Mexico.Acknowledgments. We thank Irma Coria and Silvia Vizconde for skillful assistance. Interchange of information with Dr E. Toro-Goyco, University of Puerto Rico, School of Medicin, was most helpful.     

An alkaline protease in the delayed hypersensitivity skin lesions in the guinea-pigs.

An alkaline hemoglobinolytic protease was extracted from the delayed hypersensitivity skin lesions induced by bovine gamma-globulin as an antigen in the guinea-pig. The enzyme was heat-labile and inhibited by thiol-blocking reagents. The mol.wt. was more than 100,000 and optimal pH around 9.     

Elastase digested urokinase (ED-UK)

Summary Elastase digested urokinase (ED-UK) was prepared from human high mol. wt urokinase (HMW-UK). It resembled low mol. wt urokinase (LMW-UK) in its mol. wt, specific activity, and active sites. The steady-state kinetic parameters of each enzyme for the activation of human Glu-plasminogen also resembled each other, as did their amidase parameters (with pyro-Glu-Gly-Arg-pNA).     

Elastase digested urokinase (ED-UK)

Elastase digested urokinase (ED-UK) was prepared from human high mol. wt urokinase (HMW-UK). It resembled low mol. wt urokinase (LMW-UK) in its mol. wt, specific activity, and active sites. The steady-state kinetic parameters of each enzyme for the activation of human Glu-plasminogen also resembled each other, as did their amidase parameters (with pyro-Glu-Gly-Arg-pNA).     

Denaturation map of the ribosomal DNA of Lytechinus variegatus sperm.

Electron microscopy of the partially heat denatured ribosomal DNA (rDNA) from sea urchin (Lytechinus variegatus) sperm has demonstrated that it consists of repeating units of 3.6 +/- 0.2 micron, corresponding to a mol.wt of 7.2 +/- 0.4 x 10(6). Based on differential denaturability, each repeat unit is divided into 2 regions. The larger region of 2.47 +/- 0.11 micron (mol.wt 4.9 +/- 0.22 x 10(6)) corresponds in length to the ribosomal precursor RNA of sea urchins and the smaller, GC-rich, subunit of 1.16 +/- 0.09 micrometer (mol.wt 2.3 +/- 0.18 x 10(6)) is presumed to contain non-transcribed spacer sequences.     

Tumor-derived angiogenesis factors from rat Walker 256 carcinoma: an experimental investigation and review

Summary Angiogenesis, the process of developing a hemovascular network, is an essential feature of the growth of solid tumors, and is induced by factors secreted by tumor cells. Assay procedures suitable for the investigation of angiogenesis, and for the screening of angiogenesis factors during purification are reviewed; and a number of reports describing the purification of angiogenesis factors, primarily from the rat Walker 256 carcinoma as starting material, are discussed. Work from the authors' laboratory is also presented. Walker 256 cells grown in large-scale culture were the source of a reproducible and homogeneous source of angiogenic material. Factors secreted by these cells were isolated by a series of chromatographic steps. Ion exchange chromatography on carboxymethyl-Sephadex produced two active fractions, one of which was fractionated into several macromolecular species by lectin affinity and hydrophobic adsorption chromatography. The other gave a high mol.wt, active fraction that was resolved into a low mol.wt, active component and a non-angiogenic but possibly carrier molecule with a mol.wt of 140,000. While none of the angiogenic factors were identified chemically, the results demonstrate the existence of both high and low mol.wt tumor-secreted angiogenic substances, confirming the hypothesis for tumor-induced angiogenesis and predicting potential means to interfere with the process of tumor growth.This work was supported by funds from the Monsanto Company under Agreements with Harward University and from the U.S. Public Health Service, Contract No. N01-CB-43942. We are particularly indebted to Bernard S. Wildi and Monte C. Throdahl for their advice, cooperation, and encouragement. We also thank Dr Judah Folkman for the initial supply of male mouse submaxillary glands and rat Walker carcinoma conditioned medium, for help with the CAM assays, assays in the rabbit cornea, and many helpful discussions; and R. Bretton, A. Ehrlich, B. Evans, F. Fu, N. Hay and B. Tsokanis for excellent technical assistance.Author to whom correspondence should be addressed.     

A factor potentiating serotonin in the induction of germinal vesicle breakdown in surf clam oocytes

Summary Simultaneous addition of an aliquot of body fluid obtained from the surf clam,Spisula solidissina, enhanced oocyte germinal vesicle breakdown induced with serotonin but not with KCl. When the body fluid and serotonin were added sequentially to the oocytes, potentiation did not occur. Body fluids of both males and females were effective at a 200-fold dilution. The factor is stable when treated with heat, acid, base, trypsin and pronase. It is hydrophobic and not dialyzable through tubing with a molecular weight cutoff of 1000 daltons. The factor is probably not a protein.17 November 1986Acknowledgments. This work was supported by the U.S.-Japan Cooperative Science Program, NSF INT-8211350, and Rockefeller Foundation Grant GAPS 8506. The authors thank Drs H. Shirai, T. Kishimoto, K. Sano, E. Sato and H. Ueno for valuable discussion.     

The hydrolysis of some L-amino acid-p-nitranilides with the normal and pregnant's serum aminopeptidases

Summary From 4 serum aminopeptidases (2 of pregnant and 2 of nonpregnant women's sera), the placental lysosomal (mol. wt 320,000) splits Lys-NAp only. B-Cys-NAp is hydrolyzed from the both placental enzymes, i.e. lysosomal and microsomal (mol. wt 145.000) AP. Ala-NAp is split by both nonpregnant serum AP more readily than Leu-NAp.     

Large scale preparation of oxidized streptolysin O using molecular filtration

Summary Oxidized streptolysin O, suitable for the determination of antistreptolysin O in whole blood, has been prepared from crude broth culture ofS. pyogenes by molecular filtration using membranes with nominal mol. wt limit 10,000.     

Lens regeneration from the dorsal iris inEurycea bislineata,the two-lined salamander

Summary Following lens removal from the eye of adultEurycea bislineata, the northern (USA) 2-lined salamander, it was found that this salamander has the capacity for lens regeneration. Its widespread distribution and high percentage of regenerative success suggests it as a suitable organism for the study of this differentiative phenomenon.This research was supported by N.I.H. grant EY-02534 from the National Eye Institute. We thank S.M. DiRienzo for excellent technical assistance.     

The hydrolysis of some L-amino acid-p-nitranilides with the normal and pregnant's serum aminopeptidases

From 4 serum aminopeptidases (2 of pregnant and 2 of nonpregnant women's sera), the placental lysosomal (mol. wt 320,000) splits Lys-NAp only. B-Cys-NAp is hydrolyzed from the both placental enzymes, i.e. lysosomal and microsomal (mol. wt 145,000) AP. Ala-NAp is split by both nonpregnant serum AP more readily than Leu-NAp.     

A low molecular weight glycosaminoglycan from the human aorta

Summary A low mol.wt, dialyzable glycosaminoglycan was isolated from human aorta and was found to be homogeneous on 2 dimensional electrophoresis. As judged by its electrophoretic mobilities and its hydrolysis by chondroitin sulfatase ABC, it was concluded that this hitherto unknown glycosaminoglycan is an oversulfated chondroitin sulfate.This study was supported by grants from the National Institutes of Health (GM-10374, HL-13262), U.S. Public Health Service.     

An alkaline protease in the delayed hypersensitivity skin lesions in the guinea-pigs

Summary An alkaline hemoglobinolytic protease was extracted from the delayed hypersensitivity skin lesions induced by bovine -globulin as an antigen in the guinea-pig. The enzyme was heat-labile and inhibited by thiol-blocking reagents. The mol.wt was more than 100,000 and optimal pH around 9.We thank Prof. Hideo Hayashi and Yoshimasa Morino, Kumamoto University, for valuable discussions. This work was supported in part by grants from the Ministry of Education in Japan, the Naito Research Grant. Tokyo, and the Mitsukoshi Foundation, Tokyo.     

The effect of chloroquine upon the developing lens

Summary Applied to the developing lens of the 14-day-old chick embryo, in organ culture conditions, chloquine prevented the elongation of the primary lens fibres, destroyed the equatorial ones and provoked vacuolisation and/or destruction in the epithelial cells.This work was supported by a grant from the office of the Chief Scientist, Ministry of Health, Israel