Roles of Basic Amino Acid Residues in the Activity of μ -Conotoxin GIIIA and GIIIB, Peptide Blockers of Muscle Sodium Channels

2014 ◽  
Vol 85 (4) ◽  
pp. 488-493 ◽  
Author(s):  
Kazuki Sato ◽  
Yoko Yamaguchi ◽  
Yukisato Ishida ◽  
Yasushi Ohizumi
Keyword(s):  
Amino Acid ◽  
Sodium Channels ◽  
Basic Amino Acid ◽  
Amino Acid Residues

scholarly journals Primary- and secondary-structural analysis of a unique prokaryotic metallothionein from a Synechococcus sp. cyanobacterium

1988 ◽  
Vol 251 (3) ◽  
pp. 691-699 ◽  
Author(s):  
R W Olafson ◽  
W D McCubbin ◽  
C M Kay
Keyword(s):  
Amino Acid ◽  
Metal Binding ◽  
Helical Structure ◽  
Basic Amino Acid ◽  
Cysteine Residues ◽  
Amino Acid Residues ◽  
C Terminus ◽  
Empirical Relations ◽  
Heavy Metal Binding ◽  
Synechococcus Sp

Biochemical and physiological studies of Synechococcus cyanobacteria have indicated the presence of a low-Mr heavy-metal-binding protein with marked similarity to eukaryotic metallothioneins (MTs). We report here the characterization of a Synechococcus prokaryotic MT isolated by gel-permeation and reverse-phase chromatography. The large number of variants of this molecule found during chromatographic separation could not be attributed to the presence of major isoproteins as assessed by amino acid analysis and amino acid sequencing of isoforms. Two of the latter were shown to have identical primary structures that differed substantially from the well-described eukaryotic MTs. In addition to six long-chain aliphatic residues, two aromatic residues were found adjacent to one another near the centre of the molecule, making this the most hydrophobic MT to be described. Other unusual features included a pair of histidine residues located in repeating Gly-His-Thr-Gly sequences near the C-terminus and a complete lack of association of hydroxylated residues with cysteine residues, as is commonly found in eukaryotes. Similarly, aside from a single lysine residue, no basic amino acid residues were found adjacent to cysteine residues in the sequence. Most importantly, sequence alignment analyses with mammalian, invertebrate and fungal MT sequences showed no statistically significant homology aside from the presence of Cys-Xaa-Cys structures common to all MTs. On the other hand, like other MTs, the prokaryotic molecule appears to be free of alpha-helical structure but has a considerable amount of beta-structure, as predicted by both c.d. measurements and the Chou & Fasman empirical relations. Considered together, these data suggested that some similarity between the metal-thiolate clusters of the prokaryote and eukaryote MTs may exist.

scholarly journals Thermal Behavior of Basic Amino Acid Residues of Muscle Protein during the Incubation of Fish and Poultry Minces

1998 ◽  
Vol 64 (1) ◽  
pp. 121-124 ◽  
Author(s):  
S. M. Zahangir Hossain ◽  
Tomomi Ito ◽  
Satoshi Kanoh ◽  
Eiji Niwa
Keyword(s):  
Amino Acid ◽  
Thermal Behavior ◽  
Muscle Protein ◽  
Basic Amino Acid ◽  
Amino Acid Residues

scholarly journals Three Structural Features of Functional Food Components and Herbal Medicine with Amyloid β42 Anti-Aggregation Properties

Molecules ◽  
2019 ◽  
Vol 24 (11) ◽  
pp. 2125 ◽  
Author(s):  
Kazuma Murakami ◽  
Kazuhiro Irie
Keyword(s):  
Amino Acid ◽  
Functional Food ◽  
Structural Characteristics ◽  
Salt Bridge ◽  
Basic Amino Acid ◽  
Structural Features ◽  
Amino Acid Residues ◽  
Treatment And Prevention ◽  
Food Components ◽  
Underlying Mechanisms

Aggregation of amyloid β42 (Aβ42) is one of the hallmarks of Alzheimer’s disease (AD). There are numerous naturally occurring products that suppress the aggregation of Aβ42, but the underlying mechanisms remain to be elucidated. Based on NMR and MS spectroscopic analysis, we propose three structural characteristics found in natural products required for the suppressive activity against Aβ42 aggregation (i.e., oligomerization by targeting specific amino acid residues on this protein). These characteristics include (1) catechol-type flavonoids that can form Michael adducts with the side chains of Lys16 and 28 in monomeric Aβ42 through flavonoid autoxidation; (2) non-catechol-type flavonoids with planarity due to α,β-unsaturated carbonyl groups that can interact with the intermolecular β-sheet region in Aβ42 aggregates, especially aromatic rings such as those of Phe19 and 20; and (3) carboxy acid derivatives with triterpenoid or anthraquinoid that can generate a salt bridge with basic amino acid residues such as Lys16 and 28 in the Aβ42 dimer or trimer. Here, we summarize the recent body of knowledge concerning amyloidogenic inhibitors, particularly in functional food components and Kampo medicine, and discuss their application in the treatment and prevention of AD.

Basic Amino Acid Residues Within (aa105-125) eNOS Region are Responsible for the “Flexible Arm” Movement and the Inhibition of ZnS4 Mutants

2010 ◽  
Vol 49 ◽  
pp. S101
Author(s):  
Ruslan Rafikov ◽  
Fabio V Fonseca ◽  
Sanjiv Kumar ◽  
Shawn Elms ◽  
David Fulton ◽  
...  
Keyword(s):  
Amino Acid ◽  
Arm Movement ◽  
Basic Amino Acid ◽  
Amino Acid Residues ◽  
Flexible Arm

scholarly journals M11l

2000 ◽  
Vol 191 (9) ◽  
pp. 1487-1498 ◽  
Author(s):  
Helen Everett ◽  
Michele Barry ◽  
Siow Fong Lee ◽  
Xuejun Sun ◽  
Kathryn Graham ◽  
...  
Keyword(s):  
Amino Acid ◽  
Permeability Transition ◽  
Basic Amino Acid ◽  
Viral Proteins ◽  
Myxoma Virus ◽  
Amino Acid Residues ◽  
Hydrophobic Domain ◽  
Monocyte Apoptosis ◽  
Induced Apoptosis ◽  
Knockout Virus

M11L, a novel 166–amino acid membrane-associated protein expressed by the poxvirus, myxoma virus, was previously found to modulate apoptosis after infection of rabbit leukocytes. Furthermore, infection of rabbits with an M11L knockout virus unexpectedly produced lesions with a profound proinflammatory phenotype. We show here that M11L is antiapoptotic when expressed independently of other viral proteins, and is directed specifically to mitochondria by a short COOH-terminal region that is necessary and sufficient for targeting. This targeting region consists of a hydrophobic domain flanked by basic amino acid residues, adjacent to a positively charged tail. M11L blocks staurosporine-induced apoptosis by preventing mitochondria from undergoing a permeability transition, and the mitochondrial localization of this protein is essential for this function. We show that M11L is specifically required to inhibit the apoptotic response of monocytes/macrophages during virus infection, as cells of this lineage undergo apoptosis when infected with the M11L knockout virus. As monocyte apoptosis is uniquely proinflammatory, we propose that this observation reconciles the paradoxical proapoptotic and proinflammatory phenotypes of the M11L knockout virus. We suggest that apoptosis of tissue macrophages represents an important antiviral defense, and that the inhibition of apoptosis by viral proteins can be directed in a cell-specific fashion.

Sign in / Sign up

Export Citation Format

Share Document