Showing papers on "Agmatine published in 1989"

Improved Method for HPLC Analysis of Polyamines, Agmatine and Aromatic Monoamines in Plant Tissue

Abstract: The high performance liquid chromatographic (HPLC) method of Flores and Galston (1982 Plant Physiol 69: 701) for the separation and quantitation of benzoylated polyamines in plant tissues has been widely adopted by other workers. However, due to previously unrecognized problems associated with the derivatization of agmatine, this important intermediate in plant polyamine metabolism cannot be quantitated using this method. Also, two polyamines, putrescine and diaminopropane, also are not well resolved using this method. A simple modification of the original HPLC procedure greatly improves the separation and quantitation of these amines, and further allows the simulation analysis of phenethylamine and tyramine, which are major monoamine constituents of tobacco and other plant tissues. We have used this modified HPLC method to characterize amine titers in suspension cultured carrot (Daucas carota L.) cells and tobacco (Nicotiana tabacum L.) leaf tissues.

Changes in Polyamines and Amino Acids in Scallop Adductor Muscle during Storage

Abstract: Changes in polyamines and amino acids were followed in scallop adductor muscle during storage at 5°C and 15°C. Agmatine, putrescine and cadaverine increased markedly as decomposition progressed. Arginine decreased noticeably during storage and was partly converted into ornithine and agmatine. Putrescine and ornithine were detected at levels of 0.5 to 0.7 mg/100g and 3.2 to 4.6 mg/100g, respectively, in the initial stage of decomposition and exceeded 2.2 and 15.0 mg/ 100g, respectively, at the advanced stage of decomposition regardless of the storage temperature. Putrescine and ornithine appeared to be useful as potential indicators for freshness of scallop adductor muscle.

Process for inhibiting pathological collagen cross-linking in diabetes patients

Abstract: Pathological collagen cross-linking, caused in diabetes patients on account of the higher glucose concentrations, may be inhibited by means of arginine, spermidine, creatine, or agmatine, or a pharmaceutically acceptable salt thereof, in the amount of 1 to 4 g/day.

Activation of immobilized, biotinylated choleragen A1 protein by a 19-kilodalton guanine nucleotide-binding protein

Abstract: Cholera toxin catalyzes the ADP-ribosylation that results in activation of the stimulatory guanine nucleotide-binding protein of the adenylyl cyclase system, known as Gs. The toxin also ADP-ribosylates other proteins and simple guanidino compounds and auto-ADP-ribosylates its AI protein (CTA1). All of the ADP-ribosyltransferase activities of CTAI are enhanced by 19-21-kDa guanine nucleotide-binding proteins known as ADP-ribosylation factors, or ARFs. CTAI contains a single cysteine located near the carboxy terminus. CTAI was immobilized through this cysteine by reaction with iodoacetyl-N-biotinyl-hexylenediamine and binding of the resulting biotinylated protein to avidin-agarose. Immobilized CTAI catalyzed the ARF-stimulated ADP-ribosylation of agmatine. The reaction was enhanced by detergents and phospholipid, but the fold stimulation by purified sARF-II from bovine brain was considerably less than that observed with free CTA. ADP-ribosylation of Gsa by immobilized CTAI, which was somewhat enhanced by sARF-II, was much less than predicted on the basis of the NAD:agmatine ADP-ribosyltransferase activity. Immobilized CTAI catalyzed its own auto-ADP-ribosylation as well as the ADP-ribosylation of the immobilized avidin and CTA2, with relatively little stimulation by sARF-II. ADP-ribosylation of CTA2 by free CTAI is minimal. These observations are consistent with the conclusion that the cysteine near the carboxy terminus of the toxin is not critical for ADP-ribosyltransferase activity or for its regulation by sARF-II. Biotinylation and immobilization of the toxin through this cysteine may, however, limit accessibility to Gsa or SARF-II, or perhaps otherwise reduce interaction with these proteins whether as substrates or activator.

Treatment of glucose-intermediated cross-linking of collagen in patients with diabetes mellitus by arginin, spermidin, creatin or agmatin

Abstract: The pathological crosslinking in collagen which is caused in diabetes patients by the raised glucose concentration can be inhibited by arginine, spermidine, creatine or agmatine.

Degradation of α, ω-Diguanidinoalkanes and a Novel Enzyme, Diguanidinobutane Amidinohydrolase in Pseudomonas putida

Abstract: Pseudomonas putida ATCC 12633 and some other fluorescent Pseudomonas strains utilized 1,4- diguanidinobutane (arcaine) and its homologues with 3 ~ 7 methylene groups as sole nitrogen sources. The P. putida strain produced a novel enzyme which hydrolyzed 1,4-diguanidinobutane to agmatine and urea; diguanidinobutane amidinohydrolase (EC class 3.5.3.) was proposed as the name for this enzyme. This enzyme hydrolyzed diguanidinoalkanes with 3 ~ 10 methylene groups; higher reaction rates were observed with 1,4-diguanidinobutane, 1,5-diguanidinopentane, and 1,6-diguanidinohexane. The enzyme was also active toward agmatine, although the rate was below 1 % of that toward 1,4- diguanidinobutane, and it was suggested to catalyze the hydrolysis of the higher homologues of agmatine at higher rates.The enzyme was induced by a,co-diguanidinoalkanes with 3 ~ 7 methylene groups. The substrate specificities of the enzymes individually induced by the diguanidinoalkanes with 3 ~ 7 methylene groups were very close to each oth...

Improved MethodforHPLCAnalysis ofPolyamines, Agmatine andAromatic Monoamines inPlant Tissue

Abstract: Thehighperformance liquid chromatographic (HPLC) method ofFlores andGalston (1982 Plant Physiol 69:701) fortheseparation andquantitation ofbenzoylated polyamines inplant tissues hasbeenwidely adopted byother workers. However, dueto previously unrecognized problems associated withthederivatization ofagmatine, this important intermediate inplant polyamine metabolism cannot bequantitated using this method. Also, two polyamines, putrescine anddiaminopropane, alsoarenotwell resolved using this method. Asimple modification oftheoriginal HPLCprocedure greatly improves theseparation andquantitation oftheseamines, andfurther allows thesimulation analysis of phenethylamine andtyramine, which aremajor monoamine constituents oftobacco andother plant tissues. Wehaveusedthis modified HPLCmethod tocharacterize aminetiters insuspension cultured carrot (Daucus carota L.)cells andtobacco (Nicotiana tabacum L.)leaf tissues.

γ-Guanidinooxypropylamine and NG-Methylagmatine: Novel Guanidinoamines Found in Seeds of Leguminous Plants

Abstract: A number of guanidino compounds have been found in plants. Seeds of Leguminosae are especially rich sources of these compounds1. Among them are arginine, NG-monomethylarginine, NG, NG-dimethylarginine, NG,N,G-dimethyl- arginine,γ-hydroxyarginine, homoarginine, Y-hydroxyhomoarginine and canavanine. Arginine and homoarginine are decarboxylated to form agmatine and homoagmatine respectively, both of which have already been found in some plants1-2. Decarboxylation products of other guanidino amino acids, however, have never been detected in plants.