scholarly journals The Unique Branching Patterns of Deinococcus Glycogen Branching Enzymes Are Determined by Their N-Terminal Domains

2009 ◽  
Vol 75 (5) ◽  
pp. 1355-1362 ◽  
Author(s):  
M. Palomo ◽  
S. Kralj ◽  
M. J. E. C. van der Maarel ◽  
L. Dijkhuizen
Keyword(s):  
Deinococcus Radiodurans ◽  
Catalytic Domain ◽  
Amino Acid Sequence Similarity ◽  
Side Chains ◽  
Branching Pattern ◽  
Short Side ◽  
High Amino Acid ◽  
Branching Points ◽  
Branching Patterns ◽  
Branching Enzymes

ABSTRACT Glycogen branching enzymes (GBE) or 1,4-α-glucan branching enzymes (EC 2.4.1.18) introduce α-1,6 branching points in α-glucans, e.g., glycogen. To identify structural features in GBEs that determine their branching pattern specificity, the Deinococcus geothermalis and Deinococcus radiodurans GBE (GBEDg and GBEDr, respectively) were characterized. Compared to other GBEs described to date, these Deinococcus GBEs display unique branching patterns, both transferring relatively short side chains. In spite of their high amino acid sequence similarity (88%) the D. geothermalis enzyme had highest activity on amylose while the D. radiodurans enzyme preferred amylopectin. The side chain distributions of the products were clearly different: GBEDg transferred a larger number of smaller side chains; specifically, DP5 chains corresponded to 10% of the total amount of transferred chains, versus 6.5% for GBEDr. GH13-type GBEs are composed of a central (β/α) barrel catalytic domain and an N-terminal and a C-terminal domain. Characterization of hybrid Deinococcus GBEs revealed that the N2 modules of the N domains largely determined substrate specificity and the product branching pattern. The N2 module has recently been annotated as a carbohydrate binding module (CBM48). It appears likely that the distance between the sugar binding subsites in the active site and the CBM48 subdomain determines the average lengths of side chains transferred.

The Drosophila homeobox gene optix is capable of inducing ectopic eyes by an eyeless-independent mechanism

Development ◽  
2000 ◽  
Vol 127 (9) ◽  
pp. 1879-1886 ◽  
Author(s):  
M. Seimiya ◽  
W.J. Gehring
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Gene Family ◽  
Eye Development ◽  
Ectopic Expression ◽  
Amino Acid Sequence Similarity ◽  
Sine Oculis ◽  
High Amino Acid ◽  
Independent Mechanism ◽  
Ectopic Eyes

optix is a new member of the Six/so gene family from Drosophila that contains both a six domain and a homeodomain. Because of its high amino acid sequence similarity with the mouse Six3 gene, optix is considered to be the orthologous gene from Drosophila rather than sine oculis, as previously believed. optix expression was detected in the eye, wing and haltere imaginal discs. Ectopic expression of optix leads to the formation of ectopic eyes suggesting that optix has important functions in eye development. Although optix and sine oculis belong to the same gene family (Six/so) and share a high degree of amino acid sequence identity, there are a number of factors which suggest that their developmental roles are different: (1) the expression patterns of optix and sine oculis are clearly distinct; (2) sine oculis acts downstream of eyeless, whereas optix is expressed independently of eyeless; (3) sine oculis functions synergistically with eyes absent in eye development whereas optix does not; (4) ectopic expression of optix alone, but not of sine oculis can induce ectopic eyes in the antennal disc. These results suggest that optix is involved in eye morphogenesis by an eyeless-independent mechanism.

Evaluation of popliteal artery branching patterns and a new subclassification of the ‘usual’ branching pattern

2017 ◽  
Vol 39 (9) ◽  
pp. 1005-1015
Author(s):  
Pinar Celtikci ◽  
Onur Ergun ◽  
Hasan Ali Durmaz ◽  
Isik Conkbayir ◽  
Baki Hekimoglu
Keyword(s):  
Popliteal Artery ◽  
Branching Pattern ◽  
Branching Patterns

State of the art and prospects in the development of proton‐conducting perfluorinated membranes with short side chains: A review

2020 ◽  
Author(s):  
Oleg N. Primachenko ◽  
Elena A. Marinenko ◽  
Alexey S. Odinokov ◽  
Svetlana V. Kononova ◽  
Yuri V. Kulvelis ◽  
...  
Keyword(s):  
State Of The Art ◽  
Side Chains ◽  
Short Side ◽  
Proton Conducting ◽  
Perfluorinated Membranes

scholarly journals pH-dependent regulation of the multi-subunit cation/proton antiporter Pha1 system from Sinorhizobium meliloti

Microbiology ◽  
2009 ◽  
Vol 155 (8) ◽  
pp. 2750-2756 ◽  
Author(s):  
Toshio Yamaguchi ◽  
Fuminori Tsutsumi ◽  
Péter Putnoky ◽  
Masahiro Fukuhara ◽  
Tatsunosuke Nakamura
Keyword(s):  
Sinorhizobium Meliloti ◽  
Sequence Similarity ◽  
Plant Root ◽  
Functional Expression ◽  
Amino Acid Sequence Similarity ◽  
Ph Optimum ◽  
Cation Selectivity ◽  
High Amino Acid ◽  
Alkaline Conditions ◽  
Ph Dependent

The pha1 gene cluster (pha1A′-G) of Sinorhizobium meliloti has previously been characterized as a necessary component for proper invasion into plant root tissue. It has been suggested to encode a multi-subunit K+/H+ antiporter, since mutations in the pha1 region rendered S. meliloti cells sensitive to K+ and alkali, and because there is high amino acid sequence similarity to previously characterized multi-subunit cation/H+ antiporters (Mrp antiporters). However, the detailed transport properties of the Pha1 system are yet to be determined. Interestingly, most of the Mrp antiporters are highly selective for Na+, unlike the Pha1 system. Here, we report the functional expression of the Pha1 system in Escherichia coli and the measurement of cation/H+ antiport activity. We showed that the Pha1 system is indeed a K+/H+ antiporter with a pH optimum under mildly alkaline conditions. Moreover, we found that the Pha1 system can transport Na+; this was unexpected based on previous phenotypic analyses of pha1 mutants. Furthermore, we demonstrated that the cation selectivity of the Pha1 system was altered when the pH was lowered from the optimum. The downregulation of Na+/H+ and K+/H+ antiport activities upon acidic shift appeared to occur via different processes, which might indicate the presence of distinct mechanisms for the regulation of the K+/H+ and Na+/H+ antiport activities of the Pha1 system.

scholarly journals Branching Pattern in Successive Generations of Peanuts Arachis hypogaea L.

1980 ◽  
Vol 7 (1) ◽  
pp. 41-45
Author(s):  
C. Harkness ◽  
D. J. Wright
Keyword(s):  
Genetic Variation ◽  
Environmental Effect ◽  
Genotype By Environment Interaction ◽  
Environment Interaction ◽  
Branching Pattern ◽  
Normal Pattern ◽  
Genotype By Environment ◽  
Arachis Hypogaea L ◽  
Branching Patterns ◽  
Successive Generations

Abstract Variation in branching pattern was studied in six Virginia group peanut cultivais (ssp. hypogaea var. hypogaea). Lines with genetically distinct branching patterns differing from the normal pattern were readily found in two of the cultivars. These variable lines showed no yield advantage over the normal lines. It was concluded that there is considerable genetic variation for branching pattern in Virginia peanuts. The variation could be ascribed to a range of modifier genes which can change the normal pattern of branching. There were indications of a strong environmental effect on branching pattern and of a genotype by environment interaction.

Study on Preparation and Dispersion Effect of Polycarboxylate Superplasticizer with Broken Dentiform Structure

2011 ◽  
Vol 250-253 ◽  
pp. 984-989 ◽  
Author(s):  
Zhi Yong Liu ◽  
Chong Cui ◽  
Li Li
Keyword(s):  
Carboxylic Acid ◽  
Chemical Structure ◽  
Side Chain ◽  
Side Chains ◽  
Test Results ◽  
Dispersion Effect ◽  
Anionic Polymer ◽  
Short Side ◽  
Carboxylic Acid Groups ◽  
Radical Polymerisation

Based on the analysis of the chemical structure of polycarboxylate-type SPs grafted PEO side chains, as well as sulfonic and carboxylic acid groups, a kind of polycarboxylate-based SPs grafted varied PEO side chains were synthesized by using radical polymerisation techniques.The relative dispersing effectiveness of the SPs was evaluated in cement paste and concrete by measuring paste flow and concrete slumps. The test results indicat that the copolymers with shorter PEO side chains (with 9 and 14 EO units) give lower initial dispersing power but higher time retention,with the prolonging of PEO side chains the higher initial dispersing effect and the lower time retention can be received. The excellent dispersing property and time retention of synthesized SPs for cementious systems can be achieved by grafted long side chain(with 45 EO units) integrated with short side chain(9 or 14 EO) at the backbone of anionic polymer.

scholarly journals NoPv1: a synthetic antimicrobial peptide aptamer targeting the causal agents of grapevine downy mildew and potato late blight

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Monica Colombo ◽  
Simona Masiero ◽  
Stefano Rosa ◽  
Elisabetta Caporali ◽  
Silvia Laura Toffolatti ◽  
...  
Keyword(s):  
Amino Acid ◽  
Late Blight ◽  
Downy Mildew ◽  
Negative Impact ◽  
Hybrid Approach ◽  
Cellulose Synthase ◽  
Economic Losses ◽  
Amino Acid Sequence Similarity ◽  
High Amino Acid ◽  
Peptide Aptamer

Abstract Grapevine (Vitis vinifera L.) is a crop of major economic importance. However, grapevine yield is guaranteed by the massive use of pesticides to counteract pathogen infections. Under temperate-humid climate conditions, downy mildew is a primary threat for viticulture. Downy mildew is caused by the biotrophic oomycete Plasmopara viticola Berl. & de Toni, which can attack grapevine green tissues. In lack of treatments and with favourable weather conditions, downy mildew can devastate up to 75% of grape cultivation in one season and weaken newly born shoots, causing serious economic losses. Nevertheless, the repeated and massive use of some fungicides can lead to environmental pollution, negative impact on non-targeted organisms, development of resistance, residual toxicity and can foster human health concerns. In this manuscript, we provide an innovative approach to obtain specific pathogen protection for plants. By using the yeast two-hybrid approach and the P. viticola cellulose synthase 2 (PvCesA2), as target enzyme, we screened a combinatorial 8 amino acid peptide library with the aim to identify interacting peptides, potentially able to inhibit PvCesa2. Here, we demonstrate that the NoPv1 peptide aptamer prevents P. viticola germ tube formation and grapevine leaf infection without affecting the growth of non-target organisms and without being toxic for human cells. Furthermore, NoPv1 is also able to counteract Phytophthora infestans growth, the causal agent of late blight in potato and tomato, possibly as a consequence of the high amino acid sequence similarity between P. viticola and P. infestans cellulose synthase enzymes.

The Mobility of Tryptophan and Dansyl Fluorophores in Labelled Poly(N-ethylacrylamide) and Poly(N-ethylmethacrylamide)

1993 ◽  
Vol 58 (10) ◽  
pp. 2383-2395 ◽  
Author(s):  
František Mikeš ◽  
Drahomír Výprachtický ◽  
Jan Pecka
Keyword(s):  
Conformational Changes ◽  
High Viscosity ◽  
Side Chains ◽  
Fluorescence Depolarization ◽  
Polymer Backbone ◽  
Short Side ◽  
Low Viscosity ◽  
Viscosity Range ◽  
Methylene Groups ◽  
Intramolecular Association

The mobility of tryptophan fluorophore in N-butyl-Nα-acetyltryptophanamide and in side chain of labelled poly(N-ethylacrylamide) and poly(N-ethylmethacrylamide) was investigated by the fluorescence depolarization method. The mobility of the fluorophore in the low-molecular-weight model is much higher than in side chains of the polymers. Different steric hindrance by the polymer backbone can explain the higher mobility of the fluorophore in poly(N-ethylacrylamide) and in poly(N-ethylmethacrylamide). The mobility of 5-dimethylamino-1-naphthalenesulfonamide (dansyl) fluorophore in side chains of labelled poly(N-ethylmethacrylamide) in the high-viscosity range increases with increasing number of methylene groups in side chains. The low-viscosity range, the rate s of conformational changes in short side chains (n = 2 - 7) are approximately constant and significantly decrease in long side chains (n = 10, 12). The drop in the rates is probably due to intramolecular association of the long hydrophobic chains in water.

scholarly journals Electrophysiological evidence for acidic, basic, and neutral amino acid olfactory receptor sites in the catfish.

1984 ◽  
Vol 84 (3) ◽  
pp. 403-422 ◽  
Author(s):  
J Caprio ◽  
R P Byrd
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Ictalurus Punctatus ◽  
Olfactory Receptor ◽  
Olfactory Receptors ◽  
Receptor Potential ◽  
Side Chains ◽  
Short Side ◽  
Neutral Amino Acids ◽  
Receptor Sites

Electrophysiological experiments indicate that olfactory receptors of the channel catfish, Ictalurus punctatus, contain different receptor sites for the acidic (A), basic (B), and neutral amino acids; further, at least two partially interacting neutral sites exist, one for the hydrophilic neutral amino acids containing short side chains (SCN), and the second for the hydrophobic amino acids containing long side chains (LCN). The extent of cross-adaptation was determined by comparing the electro-olfactogram (EOG) responses to 20 "test" amino acids during continuous bathing of the olfactory mucosa with water only (control) to those during each of the eight "adapting" amino acid regimes. Both the adapting and test amino acids were adjusted in concentrations to provide approximately equal response magnitudes in the unadapted state. Under all eight adapting regimes, the test EOG responses were reduced from those obtained in the unadapted state, but substantial quantitative differences resulted, depending upon the molecular structure of the adapting stimulus. Analyses of the patterns of EOG responses to the test stimuli identified and characterized the respective "transduction processes," a term used to describe membrane events initiated by a particular subset of amino acid stimuli that are intricately linked to the origin of the olfactory receptor potential. Only when the stimulus compounds interact with different transduction processes are the stimuli assumed to bind to different membrane "sites." Four relatively independent L-alpha-amino acid transduction processes (and thus at least four binding sites) identified in this report include: (a) the A process for aspartic and glutamic acids; (b) the B process for arginine and lysine; (c) the SCN process for glycine, alanine, serine, glutamine, and possibly cysteine; (d) the LCN process for methionine, ethionine, valine, norvaline, leucine, norleucine, glutamic acid-gamma-methyl ester, histidine, phenylalanine, and also possibly cysteine. The specificities of these olfactory transduction processes in the catfish are similar to those for the biochemically determined receptor sites for amino acids in other species of fishes and to amino acid transport specificities in tissues of a variety of organisms.

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