VVhen native and acid-denatured Jactate dehydregenase (LDH) were incubated with total lysosomal enzymes in vitro, amino acids from their degradation were produced at various acidic pH. The pH profile in the overall degradation of natiye LDH was markedly different from that of acid-denatured LDH. Disappearance of the 35-kDa subunit of native LDH was markedly suppressed by a low level of cystatin...

Thyroid function depends on processing of the prohormone thyroglobulin by sequential proteolytic events. From in vitro analysis it is known that cysteine proteinases mediate proteolytic processing of thyroglobulin. Here, we have analyzed mice with deficiencies in cathepsins B, K, L, B and K, or K and L in order to investigate which of the cysteine proteinases is most important for proteolytic p...

Porphyromonas gingivalis has been associated with the development of adult periodontitis and cysteine proteinases with Arg- and Lys-specific activity have been implicated as major virulence factors. In a cell sonicate of P. gingivalis W50, a complex of non-covalently associated proteins has been previously characterized. This complex is composed of a 45 kDa Arg-specific, calcium-stabilized cyst...

The fluorescent proteinase transition-state analog inhibitor, dansyl-L-argininal (DnsArgH), may be a selective probe of cysteine and serine-type proteinases in a fibrosarcoma tumor cell line (HSDM1C1). DnsArgH binds with high affinity to proteinases because of its transition-state analog properties, and on association it gives a dramatically increased fluorescent yield. The DnsArgH binding is i...

We used the cysteine proteinase B (cpb) gene family of the trypanosomatid genus Leishmania as a target to develop rapid, specific, and easy-to-use polymerase chain reaction (PCR) tests to discriminate Leishmania infantum, Leishmania donovani, Leishmania tropica, Leishmania aethiopica, and Leishmania major. Identification of all 5 Old World species and validation of intraspecies variability are ...

We have identified and characterized three stage-specific proteinases of Plasmodium falciparum that are active at neutral pH. We analyzed ring-, trophozoite-, schizont-, and merozoite-stage parasites by gelatin substrate PAGE and characterized the identified proteinases with class-specific proteinase inhibitors. No proteinase activity was detected with rings. Trophozoites had a 28 kD proteinase...

An ELISA was developed using chicken cystatin as a capture agent for the immunodiagnosis of paragonimiasis and fascioliasis. The assay detected specific antibodies to fluke cysteine proteinases without the need for purified proteinases. An ELISA plate was sensitized with chicken egg white cystatin, incubated with excretory-secretory (ES) products of adult flukes, and standard ELISA procedures w...

Cysteine proteinases and their inhibitors probably play the main role in carcinogenesis and metastasis. The metastasis process need external proteolytic activities that pass several barriers which are membranous structures of the connective tissue which includes, the basement membrane of blood vessels. Activities of the proteinases are regulated by endogenous inhibitors and activators. The imba...

In this study we have examined the tissue-destructive proteinases of human pancreatic ductal cancer cell lines derived initially from xenogenic transplants. Cancer cell organelles were isolated following nitrogen cavitation using sucrose density gradient centrifugation. Serine, cysteine, and metalloproteinases were assayed using radiolabeled protein and synthetic substrates. Tumor-induced RBC l...

A cDNA encoding a novel member of the cysteine proteinase family of proteins has been cloned from a human breast carcinoma cDNA library, by using a polymerase chain reaction-based cloning strategy. The isolated cDNA contains an open reading frame coding for a polypeptide of 321 amino acids that has been tentatively called cathepsin O. This protein presents all the structural features characteri...