scholarly journals The biosynthetic pathway of new polyamines in Caldariella acidophila

1978 ◽  
Vol 176 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Mario De Rosa ◽  
Salvatore De Rosa ◽  
Agata Gambacorta ◽  
Maria Cartenì-Farina ◽  
Vincenzo Zappia

1. Spermidine and sym-nor-spermine (1,11-diamino-4,8-diazaundecane) were identified as the major components of the polyamine pool in Caldariella acidophila, an extreme thermoacidophilic bacterium. A minor component, a new polyamine, sym-nor-spermidine (1,7-diamino-4-azaheptane) was isolated and characterized. 2. To elucidate the biosynthetic pathway, labelled methionine, putrescine, spermidine and spermine were fed to Caldariella acidophila. Incubation of the bacterium in the presence of putrescine or spermidine labelled in the tetramethylene moiety gave unlabelled sym-nor-spermidine and sym-nor-spermine, whereas the radioactivity of propylamine-labelled methionine or spermidine was incorporated into these molecules. No radioactivity was recovered in the polyamines pool when spermine was fed to Caldariella acidophila. 3. S-Adenosylmethionine and S-(5′-adenosyl)-3-methylthiopropylamine were identified as intermediates of the biosynthetic pathway; the cellular contents of the two sulphonium compounds, measured with a new isotope-dilution technique, are 60 and 15nmol/g wet wt. of cells respectively. 4. The above results are indicative of a new pathway characterized by three propylamine-transfer reactions, decarboxylated S-adenosylmethionine being the common donor of the propylamine moiety. The reactions yielding sym-nor-spermidine and sym-nor-spermine are reported for the first time. 5. The probable intermediates related to the catabolism of the tetramethylene moiety of spermidine, γ-aminobutyraldehyde, γ-aminobutyric acid or Δ1-pyrroline were not detectable. Experiments with [3-aminopropyl-3(n)-3H]spermidine trihydrochloride plus [tetramethylene-1,4-14C]spermidine trihydrochloride gave rise to an amount of labelled CO2 equivalent to the spermidine catabolized.

1992 ◽  
Vol 38 (8) ◽  
pp. 828-837
Author(s):  
Eliane Dumas-Gaudot ◽  
Abdessamad Tahiri-Alaoui ◽  
Nicole Benhamou

The occurrence of polysaccharides and sugars in the cell walls of the soil-borne pathogenic fungus Chalara elegans (deuteromycete) has been investigated at the electron microscope level, using cytochemical approaches based on the affinity of lectin or enzyme–gold complexes for some carbohydrates. Evidence for the presence of both β-1,4-glucans and chitinous components is reported here for the first time in the cell walls of chlamydospores, endoconidia, and hyphae. A minor component with N-acetyl-D-galactosamine residues is also detected in the cell walls and, as a storage product, in the cytoplasm. The spatial distribution of both cellulosic β-1,4-glucans and N-acetylglucosamine residues differs according to the fungal cells, and the present results give a more accurate description of the multilayered structure of the fungal walls (i.e., chlamydospores and hyphae). Key words: Chalara elegans, fungi, cell walls, gold cytochemistry.


1989 ◽  
Vol 109 (6) ◽  
pp. 3435-3444 ◽  
Author(s):  
T A Chatila ◽  
R S Geha ◽  
M A Arnaout

The leukocyte CD11/CD18 adhesion molecules (beta 2 integrins) are a family of three heterodimeric glycoproteins each with a distinct alpha subunit (CD11a, b, or c) and a common beta subunit (CD18). CD11/CD18 mediate crucial leukocyte adhesion functions such as chemotaxis, phagocytosis, adhesion to endothelium, aggregation, and cell-mediated cytotoxicity. The enhanced cell adhesion observed upon activation of leukocytes is associated with increased surface membrane expression of CD11/CD18, as well as a qualitative upregulation of CD11/CD18 functions. To elucidate the nature of the qualitative modifications that occur, we examined the phosphorylation status of these molecules in resting human leukocytes and upon activation with PMA or with the chemotactic peptide F-met-leu-phe (FMLP). In unstimulated cells, all three CD11 subunits were found to be constitutively phosphorylated. In contrast, phosphorylation of the common CD18 subunit was minimal. PMA induced rapid and sustained phosphorylation of CD18 that occurred at high stoichiometry, but had only minimal effects on phosphorylation of the associated CD11 subunits. FMLP also induced rapid phosphorylation of CD18, but the effect was of short duration. FMLP-induced phosphorylation of CD18 was not related to its Ca++-mobilizing effect, as CD18 phosphorylation was not observed upon treatment of leukocytes with the Ca++ ionophore, ionomycin. Phosphoamino acid analysis of CD11/CD18 in PMA- or FMLP-treated monocytes revealed a predominance of phosphoserine residues in all CD11/CD18 subunits. A small component of phosphothreonine was present in CD11c and CD18 and a minor component of phosphotyrosine was also detected in CD18 upon leukocyte activation may regulate the adhesion functions mediated by the CD11/CD18 family of molecules.


2020 ◽  
Vol 62 ◽  
pp. 32-38
Author(s):  
E. A. Dolmatov ◽  
R. B. Borzayev ◽  
A. N. Shaipov

The results of the study of the duration of the juvenile period of indigenous Chechen willow leaf pear genotypes (Pyrus salicifolia Pall.) are given in connection with the acceleration of the breeding process and the use of selected forms in pear breeding for high precocity. The studies were carried out in 2016-2019 at OOO “Orchards of Chechnya” in accordance with the Agreement on creative cooperation with the Russian Research Institute of Fruit Crop Breeding. The work was carried out in accordance with generally accepted programs and methods. The objects of the study were one-year and two-year-old pear seedlings obtained from sowing seeds of selected dwarf and low-growing local Chechen forms of willow pear (P. salicifolia Pall.), laying fruit buds on annual growths and seedlings of Caucasian pear (P. caucasica Fed.), 20 500 pcs. of each specie. The aim of the research was to study the potential of precocity of willow pear seedlings and to reveal of selected forms with the greatest degree of this trait. Stratified seeds were sown in the sowing department of the OOO “Orchards of Chechnya” production nursery in April, 2017. The seedlings were grown according to the common technology in dryland conditions on the plot with chestnut soil. The first fl owering of plants was noted in the spring, 2019. As a result of the research, for the first time on a large number of the experimental material it was found that in the off spring of the indigenous Chechen willow leaf pear genotypes, the selection of a little more than 2% of seedlings with a very short juvenile period (2 years) was possible. They are of great interest in accelerating the breeding process and in the selection of new pear varieties with high precocity. 20 willow leaf pear genotypes were selected for the further use in breeding for high precocity and as sources of the trait of short juvenile period.


1990 ◽  
Vol 55 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Zdeněk Friedl ◽  
Stanislav Böhm

The relative enthalpies of proton transfer δ ΔH0and homolytic bond strengths δDH0(B-H+) were calculated by the MNDO method for the sp and ap conformers of 4-flurobutylamine. The data obtained, along with the experimental gas phase basicities, are compared with the values predicted by the electrostatic theory. It is shown that the substituent polar effects FD on the basicities of amines are predominantly due to interactions in their protonated forms (X-B-H+) and/or radical-cations (X-B+.), those in the neutral species (X-B) playing a minor part. A contribution, which is considerably more significant in the sp conformer than in the ap conformer, arises probably also from substituent effects on the homolytic bond strength DH0(B-H+.


2009 ◽  
Vol 74 (10) ◽  
pp. 1543-1557 ◽  
Author(s):  
Herman P. Van Leeuwen ◽  
Raewyn M. Town

The degree of (de)protonation of aqueous metal species has significant consequences for the kinetics of complex formation/dissociation. All protonated forms of both the ligand and the hydrated central metal ion contribute to the rate of complex formation to an extent weighted by the pertaining outer-sphere stabilities. Likewise, the lifetime of the uncomplexed metal is determined by all the various protonated ligand species. Therefore, the interfacial reaction layer thickness, μ, and the ensuing kinetic flux, Jkin, are more involved than in the conventional case. All inner-sphere complexes contribute to the overall rate of dissociation, as weighted by their respective rate constants for dissociation, kd. The presence of inner-sphere deprotonated H2O, or of outer-sphere protonated ligand, generally has a great impact on kd of the inner-sphere complex. Consequently, the overall flux can be dominated by a species that is a minor component of the bulk speciation. The concepts are shown to provide a good description of experimental stripping chronopotentiometric data for several protonated metal–ligand systems.


2010 ◽  
Vol 18 (4) ◽  
pp. 6-8
Author(s):  
Stephen W. Carmichael

Some of the receptors on the surface of cardiac muscle cells (cardiomyocytes) mediate the response of these cells to catecholamines by causing the production of the common second messenger cyclic adenosine monophosphate (cAMP). An example of such receptors are the β1- and β2-adrenergic receptors (βARs) that are heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors. Selective stimulation of these two receptor subtypes leads to distinct physiological and pathophysiological responses, but their precise location on the surface of cardiomyocytes has not been correlated with these responses. In an ingenious combination of techniques, Viacheslav Nikolaev, Alexey Moshkov, Alexander Lyon, Michele Miragoli, Pavel Novak, Helen Paur, Martin Lohse, Yuri Korchev, Sian Harding, and Julia Gorelik have mapped the function of these receptors for the first time.


Religions ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 222
Author(s):  
Elaine M. Fisher

This article makes the case that Vīraśaivism emerged in direct textual continuity with the tantric traditions of the Śaiva Age. In academic practice up through the present day, the study of Śaivism, through Sanskrit sources, and bhakti Hinduism, through the vernacular, are generally treated as distinct disciplines and objects of study. As a result, Vīraśaivism has yet to be systematically approached through a philological analysis of its precursors from earlier Śaiva traditions. With this aim in mind, I begin by documenting for the first time that a thirteenth-century Sanskrit work of what I have called the Vīramāheśvara textual corpus, the Somanāthabhāṣya or Vīramāheśvarācārasāroddhārabhāṣya, was most likely authored by Pālkurikĕ Somanātha, best known for his vernacular Telugu Vīraśaiva literature. Second, I outline the indebtedness of the early Sanskrit and Telugu Vīramāheśvara corpus to a popular work of early lay Śaivism, the Śivadharmaśāstra, with particular attention to the concepts of the jaṅgama and the iṣṭaliṅga. That the Vīramāheśvaras borrowed many of their formative concepts and practices directly from the Śivadharmaśāstra and other works of the Śaiva Age, I argue, belies the common assumption that Vīraśaivism originated as a social and religious revolution.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Evdoxia Efstathiadou ◽  
Georgia Ntatsi ◽  
Dimitrios Savvas ◽  
Anastasia P. Tampakaki

AbstractPhaseolus vulgaris (L.), commonly known as bean or common bean, is considered a promiscuous legume host since it forms nodules with diverse rhizobial species and symbiovars. Most of the common bean nodulating rhizobia are mainly affiliated to the genus Rhizobium, though strains belonging to Ensifer, Pararhizobium, Mesorhizobium, Bradyrhizobium, and Burkholderia have also been reported. This is the first report on the characterization of bean-nodulating rhizobia at the species and symbiovar level in Greece. The goals of this research were to isolate and characterize rhizobia nodulating local common bean genotypes grown in five different edaphoclimatic regions of Greece with no rhizobial inoculation history. The genetic diversity of the rhizobial isolates was assessed by BOX-PCR and the phylogenetic affiliation was assessed by multilocus sequence analysis (MLSA) of housekeeping and symbiosis-related genes. A total of fifty fast-growing rhizobial strains were isolated and representative isolates with distinct BOX-PCR fingerpriniting patterns were subjected to phylogenetic analysis. The strains were closely related to R. anhuiense, R. azibense, R. hidalgonense, R. sophoriradicis, and to a putative new genospecies which is provisionally named as Rhizobium sp. I. Most strains belonged to symbiovar phaseoli carrying the α-, γ-a and γ-b alleles of nodC gene, while some of them belonged to symbiovar gallicum. To the best of our knowledge, it is the first time that strains assigned to R. sophoriradicis and harbored the γ-b allele were found in European soils. All strains were able to re-nodulate their original host, indicating that they are true microsymbionts of common bean.


Author(s):  
Nooreddine Iskandar ◽  
Tatiana Rahbany ◽  
Ali Shokor

Abstract Background: Due to the common instability caused by political and security issues, Lebanese hospitals have experienced acts of terrorism multiple times. The most recent Beirut Explosion even forced several hospitals to cease operations for the first time in decades—but studies show the preparedness levels for such attacks in similar countries are low. Objective: The aim of this study is to explore the experience of Lebanese hospitals with terrorist attacks. Methods: This qualitative study used semi-structured interviews with various stakeholders to assess their experience with terrorist bombings. Data was analyzed using the thematic analysis method. Results: The researchers found that Lebanese hospitals vary greatly in their structures and procedures. Those differences are a function of 3 contextual factors: location, culture, and accreditation status. Hospitals found near ‘dangerous zones’ were more likely to be aware and to have better response to such events. A severe lack of communication, unity of command, and collaboration between stakeholders has made the process fragmented. Conclusion: The researchers recommend a larger role for the Ministry of Public Health (MOPH) in this process, and the creation of a platform where Lebanese organizations can share their experiences to improve preparedness and resilience of the Lebanese healthcare system in the face of terrorism.


1994 ◽  
Vol 8 (1) ◽  
pp. 33-35
Author(s):  
Noel B Hershfield

Endoscopic retrograde cholangiopancreatography (ERCP) is established as the method of choice to investigate the biliary tree when obstruction is suspected. On rare occasions, the papilla cannot be entered because of anatomical or pathological abnormalities. This report describes endoscopic fistulotomy or the suprapapillary punch that has been carried out at the Foothills Hospital in Calgary, Alberta, on 30 of 623 patients referred for ERCP for conditions causing obstruction of the common bile duct or suspected obstruction of the common bile duct. The following communication also describes the method of suprapapillary punch or endoscopic fistulotomy. Results have been excellent with only one complication, a minor attack of pancreatitis after the procedure. In summary, the suprapapillary punch or fistulotomy is a safe and useful method for entering the common bile duct when access by the usual method is impossible.


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