scholarly journals Serum Amino Acid Profiling in Patients with Alkaptonuria Before and After Treatment with Nitisinone

2018 ◽  
pp. 109-117 ◽  
Author(s):  
A. S. Davison ◽  
B. P. Norman ◽  
E. A. Smith ◽  
J. Devine ◽  
J. Usher ◽  
...  
1990 ◽  
Vol 22 (3) ◽  
pp. 209-210 ◽  
Author(s):  
PEGGY A. MILLER-GRABER ◽  
LAURIE M. LAWRENCE ◽  
ELAINE KURCZ ◽  
RACHEL KANE ◽  
KARIN BUMP ◽  
...  

1985 ◽  
Vol 5 (10-11) ◽  
pp. 855-865 ◽  
Author(s):  
L. Ping Chung ◽  
Kenneth B. M. Reid

The binding and cofactor activities of C4b-binding protein were examined before and after limited proteolysis by pepsin, trypsin and chymotrypsin. The major fragments generated were characterized by amino acid sequencing, thus establishing the precise points of limited proteolysis. These studies allow a tentative assignment of the cofactor activity site to the residues 177–322 of the 549 amino acid long chain of C4b-binding protein but indicated that residues in the region 332–395 are important in the binding activity.


eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Bargavi Thyagarajan ◽  
Jesse D Bloom

Influenza is notable for its evolutionary capacity to escape immunity targeting the viral hemagglutinin. We used deep mutational scanning to examine the extent to which a high inherent mutational tolerance contributes to this antigenic evolvability. We created mutant viruses that incorporate most of the ≈104 amino-acid mutations to hemagglutinin from A/WSN/1933 (H1N1) influenza. After passaging these viruses in tissue culture to select for functional variants, we used deep sequencing to quantify mutation frequencies before and after selection. These data enable us to infer the preference for each amino acid at each site in hemagglutinin. These inferences are consistent with existing knowledge about the protein's structure and function, and can be used to create a model that describes hemagglutinin's evolution far better than existing phylogenetic models. We show that hemagglutinin has a high inherent tolerance for mutations at antigenic sites, suggesting that this is one factor contributing to influenza's antigenic evolution.


Metabolites ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 114 ◽  
Author(s):  
Kristen Clermont ◽  
Yaxin Wang ◽  
Siming Liu ◽  
Zhenzhen Yang ◽  
Claude dePamphilis ◽  
...  

Parasitic weeds of the family Orobanchaceae attach to the roots of host plants via haustoria capable of drawing nutrients from host vascular tissue. The connection of the haustorium to the host marks a shift in parasite metabolism from autotrophy to at least partial heterotrophy, depending on the level of parasite dependence. Species within the family Orobanchaceae span the spectrum of host nutrient dependency, yet the diversity of parasitic plant metabolism remains poorly understood, particularly during the key metabolic shift surrounding haustorial attachment. Comparative profiling of major metabolites in the obligate holoparasite Phelipanche aegyptiaca and the facultative hemiparasite Triphysaria versicolor before and after attachment to the hosts revealed several metabolic shifts implicating remodeling of energy and amino acid metabolism. After attachment, both parasites showed metabolite profiles that were different from their respective hosts. In P. aegyptiaca, prominent changes in metabolite profiles were also associated with transitioning between different tissue types before and after attachment, with aspartate levels increasing significantly after the attachment. Based on the results from 15N labeling experiments, asparagine and/or aspartate-rich proteins were enriched in host-derived nitrogen in T. versicolor. These results point to the importance of aspartate and/or asparagine in the early stages of attachment in these plant parasites and provide a rationale for targeting aspartate-family amino acid biosynthesis for disrupting the growth of parasitic weeds.


2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Chang Xu ◽  
Xin Li ◽  
Debin Zeng ◽  
Ying Liu ◽  
Yuhang Gao ◽  
...  

Type 2 diabetes mellitus (T2DM) has become a major disease threatening human health worldwide. At present, the treatment of T2DM cannot cure diabetes and is prone to many side effects. Psidium guajava L. leaves have been reported to possess hypoglycemic activity, and they have been widely used in diabetes treatment in the folk. However, the antidiabetic mechanism has not been clearly explained. Also, the change in amino acid profile can reflect a metabolic disorder and provide insights into system-wide changes in response to physiological challenges or disease processes. The study found that P. guajava L. leaves can decrease fasting blood glucose and lipid levels in type 2 diabetic rats induced by streptozotocin. Through the analysis of amino acid profiling following 20 days of gavage administration, the concentration data were modeled by principal component analysis and orthogonal partial least squares discriminant analysis to find the different metabolites and related metabolic pathways (including cysteine and methionine metabolism, valine, leucine, and isoleucine biosynthesis, phenylalanine, tyrosine, and tryptophan biosynthesis) for the explanation of the hypoglycemic mechanism of P. guajava L., which provides an experimental and theoretical basis for diabetes prediction and for the development of new drugs for the treatment of diabetes.


1957 ◽  
Vol 35 (1) ◽  
pp. 1005-1016 ◽  
Author(s):  
J. B. Derrick ◽  
Audrey P. Hanley

Observations have been made on the specific free amino acids (chromatographic analysis) and other nitrogenous constituents in the serum and urine of normal and arthritic men under controlled dietary conditions, before and after a glycine load and adrenocorticotropin administered separately and together.Differences in the metabolism of amino acids between normal individuals and arthritics, particularly of alanine, proline, glutamic acid, taurine, and possibly tyrosine (and/or tryptophan) and cystine, were apparent. The differences were largely confined to the non-essential amino acids. Concomitant increases seen in the serum levels and in the excretion of several amino acids, in response to a load of a single amino acid, indicate that the increases in excretion are more than a matter of competition for reabsorption in the kidney. A prerenal phenomenon appears to be involved, possibly interconversion of amino acids. This concept is supported by the evidence that the increases in the serum levels were restricted to the non-essential amino acids.


1957 ◽  
Vol 35 (11) ◽  
pp. 1005-1016 ◽  
Author(s):  
J. B. Derrick ◽  
Audrey P. Hanley

Observations have been made on the specific free amino acids (chromatographic analysis) and other nitrogenous constituents in the serum and urine of normal and arthritic men under controlled dietary conditions, before and after a glycine load and adrenocorticotropin administered separately and together.Differences in the metabolism of amino acids between normal individuals and arthritics, particularly of alanine, proline, glutamic acid, taurine, and possibly tyrosine (and/or tryptophan) and cystine, were apparent. The differences were largely confined to the non-essential amino acids. Concomitant increases seen in the serum levels and in the excretion of several amino acids, in response to a load of a single amino acid, indicate that the increases in excretion are more than a matter of competition for reabsorption in the kidney. A prerenal phenomenon appears to be involved, possibly interconversion of amino acids. This concept is supported by the evidence that the increases in the serum levels were restricted to the non-essential amino acids.


2004 ◽  
Vol 96 (5) ◽  
pp. 1643-1650 ◽  
Author(s):  
Irene C. Solomon

Activation of ionotropic excitatory amino acid (EAA) receptors in pre-Bötzinger complex (pre-BötC) not only influences the eupneic pattern of phrenic motor output but also modifies hypoxia-induced gasping in vivo by increasing gasp frequency. Although ionotropic EAA receptor activation in this region appears to be required for the generation of eupneic breathing, it remains to be determined whether similar activation is necessary for the production and/or expression of hypoxia-induced gasping. Therefore, we examined the effects of severe brain hypoxia before and after blockade of ionotropic EAA receptors in the pre-BötC in eight chloralose-anesthetized, deafferented, mechanically ventilated cats. In each experiment, before blockade of ionotropic EAA receptors in the pre-BötC, severe brain hypoxia (6% O2 in a balance of N2 for 3-6 min) produced gasping. Although bilateral microinjection of the broad-spectrum ionotropic EAA receptor antagonist kynurenic acid (20-100 mM; 40 nl) into the pre-BötC eliminated basal phrenic nerve discharge, severe brain hypoxia still produced gasping. Under these conditions, however, the onset latency to gasping was increased ( P < 0.05), the number of gasps was reduced for the same duration of hypoxic gas exposure ( P < 0.05), the duration of gasps was prolonged ( P < 0.05), and the duration between gasps was increased ( P < 0.05). These findings demonstrate that hypoxia-induced gasping in vivo does not require activation of ionotropic EAA receptors in the pre-BötC, but ionotropic EAA receptor activation in this region may modify the expression of the hypoxia-induced response. The present findings also provide additional support for the pre-BötC as the primary locus of respiratory rhythm generation.


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