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F Fiedler

Publications and source records attributed to F Fiedler.

At least 109 records · Page 6Linked to original sources
PubMed1981

On the various forms of the glandular kallikrein from autolyzed porcine pancreas.

Kallikrein C, a minor form of the glandular kallikrein isolated form autolyzed porcine pancreas, has the same amino acid composition a porcine pancreatic beta-kallikreins A and B and comparable specific activity, but a much lower carbohydrate content. Dodecyl sulfate electrophoresis of the reduced enzyme indicated that it is composed of the same two polypeptide chains as the other pancreatic beta-kallikreins of the pig. The carbohydrate content of the two chains of beta-kallikrein B has been determined. Both the A and the B chain of beta-kallikreins from autolyzed porcine pancreas exist in a high-molecular (h) and a low-molecular (1) form which evidently differ only in their carbohydrate content. beta-Kallikrein B has the composition AhBh, beta-kallikrein A, AhB1, and beta-kallikrein C, A1B1. The properties of kallikrein III from porcine pancreas, recently described by Kira et al. (Adv. Exp. Med. Biol. 120A (1979) 273--290), indicate that is is the fourth conceivable form, A1Bh. A preparation of porcine pancreatic kallikrein d2 was found to have a specific activity comparable to that of other kallikrein preparations. Besides a main component migrating like pancreatic beta-kallikrein A, it also contained beta-kallikreins B and C. All four species of chains were observed to occur in this batch of the enzyme. Zuber and Sache (Biochemistry 13 (1974) 3098--3110) reported the resolution of porcine pancreatic kallikreins d1 and d2 into three electrophoretic components each after reduction. Evidently, all these preparations consist of a mixture of several forms of two-chain pancreatic beta-kallikrein.

Amino Acids↗
PubMed1980

Isolation and characterization of native single-chain porcine pancreatic kallikrein, another possible precursor of urinary kallikrein.

Porcine pancreatic kallikrein B' was isolated from partially purified prokallikrein B activated "spontaneously" (most probably due to the action of some contaminating proteinase). Upon dodecyl sulfate electrophoresis after reduction, the enzyme migrated like the single-chain alpha-kallikreins A from submandibular glands and urine of the pig, indicating an apparent molecular weight of about 36,000. Evidently, porcine pancreatic kallikrein B' is also a single-chain alpha-kallikrein, in contrast to the two-chain beta-kallikrein obtained by the usual isolation procedure from autolyzed porcine pancreas. The amino acid composition of kallikrein B' is very similar to that of the other porcine glandular kallikreins and it too contains glucosamine. The specific activities of kallikrein B', as measured under various conditions, also resemble closely those of porcine urinary and submandibular kallikreins, as do the rates of the enzyme-catalyzed hydrolyses of various amino acid ester substrates. During the hydrolysis of Bz-LysOMe or low concentrations of Bz-ArgOEt, the same strange biphasic course of the reaction is seen, as observed previously in the case of the other single-chain porcine kallikreins. Consequently, the properties of native porcine pancreatic kallikrein are well consistent with the suggestion that urinary kallikrein represents filtered enzyme of pancreatic and submandibular origin. Further available evidence for this and the alternative hypothesis of synthesis of urinary kallikrein in the kidney is discussed.

Amino Acids↗
PubMed1979

DNA-DNA homology studies among strains of Arthrobacter and Brevibacterium.

Sixteen named strains of Arthrobacter and two strains of Brevibacterium were investigated by nucleic acid hybridisation. The Arthrobacter strains show homology values ranging between 11 and 55% to the type strain A. globiformis DSM 20124 (ATCC 8010), indicating only a low to moderate relationship. Two strains of A. globiformis, DSM 20124 and DSM 20125, exhibit only poor relationship to one another (30%). Among all the Arthrobacter strains the homology data range between 10 to 70% demonstrating separate status of almost all species. Only A. polychromogenes DSM 20136 was found to be a subspecies of A. oxydans DSM 20119. The type strain of A. citreus, DSM 20133 shows a remarkable lack of homology to four other strains of A. citreus, deposited as ATCC 15170, ATCC 17775, ATCC 21040 and ATCC 21348 (11--13%) which themselves can be separated into two groups according to the homology data (24--31%). Each of the two strains of Brevibacterium share high genetic relatedness with one of these A. citreus groups (71 and 73%, respectively). According to the DNA-DNA homology data, most of the species of Arthrobacter can actually be ranged taxonomically as species.

Arthrobacter↗
PubMed1979

The isolation and properties of pig submandibular kallikrein.

The kallikrein from pig submandibular glands was highly purified, with an overall yield of 31%. Affinity chromatography on bovine basic pancreatic trypsin inhibitor linked to Sepharose 4B was an especially effective step in the purification procedure, giving a purification factor of 80. The enzyme is a single-chain molecule, occurring, as does pig urinary kallikrein, as a major B-form of apparent mol.wt. 39600 and minor amounts of an A-form of apparent mol.wt. 35900; the two forms can be separated by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. The amino acid composition of pig submandibular kallikrein is very similar to, but not quite identical with, that of the two-chain beta-kallikrein isolated from pig pancreatic autolysates. Submandibular kallikrein contains notably more glucosamine and hexoses than does pancreatic beta-kallikrein. Submandibular kallikrein, and also urinary kallikrein, exhibit an unusual biphasic hydrolysis of substrate esters that is not shared by pancreatic beta-kallikrein. For the submandibular enzyme, the K(m) for the initial reaction phase of the hydrolysis of alpha-N-benzoyl-l-arginine ethyl ester is 0.15+/-0.01mm (mean+/-s.e.m.), but rises to 0.69+/-0.04mm (mean+/-s.e.m.) in the stationary reaction phase; the V(max.) does not differ significantly between the two phases. The esterolytic activities of submandibular and urinary kallikreins on a number of esters of different amino acids resemble each other much more closely than those of pancreatic beta-kallikrein.

Amino Acids↗
PubMed1979

Substrate specificity of porcine pancreatic kallikrein.

The primary specificity of porcine pancreatic kallikrein is directed predominantly against arginyl and much less so against lysyl bonds. In addition, the enzyme exhibits pronounced secondary specificity for a bulky residue, preferentially phenylalanine, in position P2 of substrates. This feature is found also in porcine submandibular and urinary and in human urinary kallikrein, but not in bovine trypsin. Residues in P3 and P1' and P1' to P3' also affect hydrolysis by pancreatic kallikrein distinctly more than tryptic hydrolysis. The hexapeptide Pro-Phe-Arg-Ser-Val-Gln with the sequence of bovine kininogen around the C-terminus of kinin contains all the structural elements essential for the interaction with kallikrein, and even glutamine appears dispensable. In contrast to ester models for this site, peptidyl methionine esters with the structure of kininogen towards the N-terminus of kinin, notably bulky leucine in P2, are very poor kallikrein substrates, and appear to be of no value as models for the cleavage of kininogen under formation of kallidin.

Amino Acid Sequence↗
PubMed1978

[Peptidoglycan type and cell wall polysaccharide composition of Cellulomonas cartalyticum and some coryneform organisms (author's transl)].

Cellulomonas cartalyticum was found to contain a peptidoglycan type different from that of the other species of Cellulomonas. The diamino acid is lysin instead of ornithine and the interpeptide bridge consists of D-Asp-D-Ser. The same peptidoglycan type occurs in Corynebacterium manihot, Brevibacterium liticum and Arthrobacter luteus. These non cellulolytic organisms are most likely not closely related with Cellulomonas cartalyticum, as indicated by the very different G +C content of their DNA, although they formed a narrow cluster including C. cartalyticum when numeric taxonomical methods were applied.

Actinomycetales↗
PubMed1978

Peptide esters and nitroanilides as substrates for the assay of human urinary kallikrein.

Ac-Phe-ArgOMe is hydrolyzed much faster than are Bz-ArgOEt, Z-ArgOMe, or Ac-Gly-ArgOMe by the kallikrein from human urine. The synthesis of Ac-Phe-ArgOEt is described. Hydrolysis of this substrate can be conveniently monitored by a coupled spectrophotometric procedure. Increase in absorbance is linear with time and proportional to the amount of kallikrein up to a deltaA366 of at least 0.22/10 min. This assay for human urinary kallikrein is 46-fold more sensitive than that based on Bz-ArgOEt and 38-fold more sensitive than that with D-Val-Leu-Arg-p-nitroanilide. A number of other arginine p-nitroanilides are hydrolyzed by this enzyme at still lower rates. The assay of human urinary kallikrein with D-Val-Leu-ArgOEt is about a factor of two less sensitive than the assay with Ac-Phe-ArgOEt. This also holds for Z-TyrONp, which displays a rapid spontaneous hydrolysis. Furthermore, the rate of the enzymic reaction with Z-TyrONp drops off rapidly.

Anilides↗
PubMed1977

Inhibition of three porcine glandular kallikreins by chloromethyl ketones.

In accordance with its lack of inhibitory activity against pig pancreatic kallikrein, Tos-LysCH2C1 has been shown also not to inhibit the porcine kallikreins from submandibular glands and from urine. Peptidyl-lysyl-chloromethanes, however, have been demonstrated to be irreversible inhibitors of all three enzymes. The rates of inhibition increase with increasing size of the amino acid residue in position P2 of the inhibitors. As expected from the known primary specificity of the pancreatic kallikrein, Gly-Val-ArgCH2C1 was found to be the most potent of the inhibitors studies. Kinetic constants for the inhibiton of the three porcine glandular kallikreins have been determined for two of the compounds. All data obtained suggest a close similarity of the three glandular kallikreins of the pig and even a possible identity of the enzymes from submandibular glands and from urine.

Animals↗
PubMed1976

[On the secretion of BAEE-esterase activity (kallikrein) in normal human parotid glands in rest and under stimulation (author's transl)].

Kallikrein is an important mediator in microcirculation. Therefore, this work has been concerned with the excretion of kallikrein from human parotid glands. In 40 healthy persons kallikrein concentrations in resting parotid saliva were estimated. Subsequently, the glands were stimulated either by ascorbic acid or by subcutaneous injection of pilocarpin and the changes in BAEE-esterase activity were measured. The results show a significant increase of excreted enzyme on stimulation. Continuous stimulation, however, leads to exhaustion of the capacity of the glands within 40 min. After cessation of stimulation basal secretion rates are restored in the next 15 min. Kallikrein secretion is compared to the secretion of total protein, lysozym and immunglobulin A.

Adolescent↗
PubMed1975

Characterization of pig pancreatic kallikreins A and B.

Pig pancreatic kallikreins A and B are both composed of the same 229 amino acids, a figure resembling the number of amino acid residues found in other serine proteinases of pancreas. Both forms of the enzyme contain N-terminal isoleucine and alanine and C-terminal leucine/serine (about half a mol each per mol kallikrein) and proline. Values for the glucosamine content of the kallikreins obtained on the amino acid analyzer after hydrolysis with p-toluenesulfonic acid, a procedure also used for the determination of amide ammonia, agreed with those determined by a gas-chromatographic method. Neuraminidasetreated kallikrein B differs from the A form only in containing roughly double the amount (on the average a total of 11.5 vs. 5.6% by weight) of carbohydrate (glucosamine, mannose, galactose, and fucose) and possibly by a higher content (20 vs. 17 residues) of amide ammonia. From the composition, molecular weights of 26800 and 28600 are calculated for sialic-acid-free kallikreins A and B, respectively, and of 25300 for the protein part of kallikrein. The molar absorbance of both forms of the enzyme has been determined as (50.6 +/- 1.3) X 10(3)M-1 cm-1 at 280 nm. A comparison of kallikreins A and B with kallikreins d1 and d2 described by Zuber and Sache reveals as principal difference a much lower specific activity of the latter preparations with all reagents tested. Conceivably, the reported lower carbohydrate contents of kallikreins d1 and d2 and their separation into three instead of two major subunits are related to this finding.

Amino Acids↗