Tissue kallikrein

L-kininogen Tissue kallikrein kallidin (KRPPGFSPFR) B2 receptor... 

B2 knockout embryos subjected to salt stress in utero show suppressed renin expression and an abnormal kidney phenotype and develop early postnatal hypertension. Consistently, although basal bradykinin formation is defective tissue kallikrein-null mice have normal blood pressure however suffer from cardiovascular abnormalities. However suggesting a function of kinin signaling during development. 

The 68-kDa t-PA molecule, although synthesized as a single chain, undergoes modification to result in A and B polypeptide chains connected by a single disulfide bridge (36). This modification is mediated by factor Xa, tissue kallikrein, and directly on the surface of a thrombus by plasmin (37). The affinity of the A chain... 

D. C. Pimenta, M. A. Juliano, L. Juliano, Hydrolysis of Somatostatin by Human Tissue Kallikrein after the Amino Acid Pair Phe-Phe , Biochem. J. 1997, 327, 27-30. 

Plasma kallikrein [EC 3.4.21.34], also known as kinino-genin and serum kallikrein, catalyzes the hydrolysis of Arg—Xaa and Lys—Xaa bonds in polypeptides. This includes the Lys—Arg and Arg—Ser bonds in human kininogen, thus producing bradykinin. Tissue kallikrein [EC 3.4.21.35] catalyzes the hydrolysis of peptide bonds, preferentially Arg—Xaa, in smaU-molecule substrates. It catalyzes the breaking of the appropriate bonds in kininogen resulting in the release of lysyl-bradykinin. 

Kallikreins are present in plasma and in several tissues, including the kidneys, pancreas, intestine, sweat glands, and salivary glands. Plasma prekallikrein can be activated to kallikrein by trypsin, Hageman factor, and possibly kallikrein itself. In general, the biochemical properties of tissue kallikreins are different from those of plasma kallikreins. Kallikreins can convert prorenin to active renin, but the physiologic significance of this action has not been established. 

Each kinin is formed from a kininogen by the action of a different enzyme. Bradykinin is released by plasma kallikrein, lysylbradykinin by tissue kallikrein, and methionyllysylbradykinin by pepsin and pepsin-like enzymes. The three kinins have been found in plasma and urine. Bradykinin is the predominant kinin in plasma, whereas lysylbradykinin is the major urinary form. 

Another kinin, Lys-bradykinin (also known as kallidin), is produced via the action of the tissue-kallikrein enzyme on LMWK. This enzyme is found in many tissues, either in the form of a precursor requiring activation or as an active enzyme. In contrast to plasma kallikrein, which preferentially acts upon HMWK, tissue kallikrein can release kallidin from either HMWK or LMWK. Through the action of aminopeptidases, kallidin can subsequently be converted directly into bradykinin. This enzyme is present in both the plasma and on the surface of epithelial cells. 

Discovery of the Human Tissue Kallikrein Gene Locus ... 

The Tissue Kallikreins in the Context of Other Serine Proteases in the... 

Mastomys is an African rodent that is intermediate in size and that has physical characteristics between the mouse and rat. It has been studied because of the presence of an androgen-responsive prostate in the female. Fahnestock reported the cloning of cDNAs from Mastomys. Two of these cDNAs were expressed in the kidney as well as the submandibular gland, and one is hypothesized to code for a true tissue kallikrein [22]. A third kallikrein was found only in the submandibular gland. DNA sequence analysis and hybridization studies demonstrate that Mastomys represents an interesting hybrid between mouse and rat [22],... 

No more than three tissue kallikreins were identified up to now in the guinea pig [26]. Two kallikreins were cloned in the horse—a renal kallikrein [27] and a horse prostate kallikrein [28], which is a homologue of human PSA. Southern blot analysis data detected KLK2- and A LA i-positive bands in several nonhuman primate species including macaque, orangutan,... 

Summary of Human Tissue Kallikrein Protein Characteristics... 

Fig. 2. Expression map of human tissue kallikreins in a variety of tissues, as determined by reverse transcriptase polymerase chain reaction. The relative semiquantitative expression levels for each gene are indicated.

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