| isolation and properties of an angiotensin ii-cleaving peptidase from mesquite pollen. | biochemical studies of pollen proteins have been focused, primarily, in investigating their roles as allergens. these molecules, some of which have enzymatic activity, act as antigens and initiate the production of ige antibodies, leading to allergic and/or asthmatic responses. included in this mixture of proteins are proteinases which, although they may or may not be allergenic, could still be involved in airway dysfunction. we have isolated an arginine-specific endopeptidase to homogeneity fro ... | 1995 | 7695924 |
| purification and characterization of a novel peptidase (iimes) from mesquite (prosopis velutina) pollen. | although the mesquite plant (prosopis velutina) is not as widely distributed as some other allergenic species, its pollen can induce serious pollinosis in areas where it is localized. we previously isolated and characterized a peptidase from mesquite pollen with trypsin-like specificity (peptidase imes) (matheson, n., schmidt, j., and travis, j. (1995) am. j. respir. cell mol. biol. 12, 441-448). now we have characterized a second enzyme with specificity for hydrophobic residues (mesquite pollen ... | 1998 | 9642233 |
| vulnerability to xylem cavitation and the distribution of sonoran desert vegetation. | we studied 15 riparian and upland sonoran desert species to evaluate how the limitation of xylem pressure (psi(x)) by cavitation corresponded with plant distribution along a moisture gradient. riparian species were obligate riparian trees (fraxinus velutina, populus fremontii, and salix gooddingii), native shrubs (baccharis: spp.), and an exotic shrub (tamarix ramosissima). upland species were evergreen (juniperus monosperma, larrea tridentata), drought-deciduous (ambrosia dumosa, encelia farino ... | 2000 | 10991900 |
| structural characterization of mesquite (prosopis velutina) gum and its fractions. | structural and physicochemical characteristics of mesquite gum (from prosopis velutina) were investigated using ft-ir spectroscopic, mass spectrometric and chromatographic methods. four fractions (f-i, f-iia, f-iib and f-iii) were isolated by hydrophobic interaction chromatography. the samples were characterized and analyzed for their monosaccharide and oligomers composition by high performance anion-exchange chromatography with pulsed amperometric detection (hpaec-pad). l-arabinose (l-ara) and ... | 2008 | 18446807 |
| protection from livestock fails to deter shrub proliferation in a desert landscape with a history of heavy grazing. | desertification is often characterized by the replacement of mesophytic grasses with xerophytic shrubs. livestock grazing is considered a key driver of shrub encroachment, although most evidence is anecdotal or confounded by other factors. mapping of velvet mesquite (prosopis velutina) shrubs in and out of exclosures in 1932, 1948, and 2006 in semiarid grasslands of southeastern arizona, usa, afforded the opportunity to quantify livestock grazing effects on mesquite proliferation over 74 years i ... | 2011 | 21830707 |