1. trans-4-Hydroxy-l-proline was found to occur in the bound state in the leaves of sandal (Santalum album L.), in which large amounts of free cis-4-hydroxy-l-proline are also present. 2. Bound trans-4-hydroxy-l-proline was present, associated mainly with a ;wall' fraction and a ;soluble' fraction roughly in equal proportions. 3. Bound proline is present only in small amounts in the ;soluble' f...

Proline racemase (ProR) is a member of the pyridoxal 5'-phosphate-independent racemase family, and is involved in the Stickland reaction (fermentation) in certain clostridia as well as the mechanisms underlying the escape of parasites from host immunity in eukaryotic Trypanosoma. Hydroxyproline epimerase (HypE), which is in the same protein family as ProR, catalyzes the first step of the trans-...

background: microwave thermotherapy has been gradually used in radiotherapy and it is reported that microwave radiation increases bone demineralization rate independently of temperature. furthermore, it becomes more and more widespread that the damage caused by the synergistic effect of microwave radiation and hypergravity. the experiment was designed to investigate the effect of microwave radi...

Approximately half the proline residues in fibrillar collagen are hydroxylated. The predominant form is 4-hydroxyproline, which helps fold and stabilize the triple helix. A minor form, 3-hydroxyproline, still has no clear function. Using peptide mass spectrometry, we recently revealed several previously unknown molecular sites of 3-hydroxyproline in fibrillar collagen chains. In fibril-forming ...

The carbohydrate moiety of secretory arabinogalactan protein in bean seedlings (Phaseolus vulgaris L. cv. Prélude) is attached to the peptide backbone through hydroxyproline, serine, and threonine. Hydroxyproline-linked side chains, consisting of arabinose, galactose, glucose, and rhamnose, comprise the major part of the sugar residues. These hydroxyproline glycosides differ from those in non-e...

The amount of hydroxyproline in urine is an index to the catabolism of collagen. Diseases like acromegaly, hyperthyroidism, osteoporesis, Marfan’s syndrome which are characterized by changes in the metabolism of collagen have made the urinary hydroxyproline determinations more valuable for clinical purposes (1). The profile of urinary hydroxyproline excretion during the 24-hr period in normal r...

When disks of carrot (Daucus carota) phloem parenchyma are incubated for 6 days there is a 10-fold increase in cell wall hydroxyproline due to the synthesis and secretion of hydroxyproline-containing macromolecules. The synthesis of these molecules and their secretion are demonstrated by measuring the kinetics of incorporation and of chase of (14)C-proline and hydroxyproline in different fracti...

Stetten & Schoenheimer (1943) fed [15N]proline to young rats and showed it to be a good source of the hydroxyproline of the carcass protein. Later, Stetten (1949) found that the efficiency of dietary [15N]hydroxyproline was less than one-twentieth of that of proline as a precursor of collagen hydroxyproline. These findings are of considerable interest since they are contrary to the general obse...

Ethylene production and cell wall hydroxyproline-rich glycoprotein (HRGP) biosynthesis are greatly enhanced in melon (Cucumin melo cv. Cantaloup charentais) seedlings infected with Colletotrichum lagenarium. Short-term experiments performed in the presence of specific inhibitors of the ethylene pathway from methionine, namely l-canaline and amino-ethoxyvinylglycine, indicate that under non-toxi...

The presence of hydroxyproline, and the determination of the ratio of the secondary amino acids proline to hydroxyproline, in amino acid hydrolysates specifically identifies collagen and collagen peptides. o-Phthalaldehyde, and then 9-fluorenylmethyl chloroformate, were used to carry out sequential prederivatization of amino acid hydrolysates in an in-line high-performance liquid chromatography...