Characterization of the Amino Acids fromNeisseria meningitidisMsrA Involved in the Chemical Catalysis of the Methionine Sulfoxide Reduction Step

ABSTRACTWe determined the enzymatic characteristics of an industrially important biocatalyst, α-ketoglutarate-dependentl-isoleucine dioxygenase (IDO), which was found to be the enzyme responsible for the generation of (2S,3R,4S)-4-hydroxyisoleucine inBacillus thuringiensis2e2. Depending on the amino acid used as the substrate, IDO catalyzed three different types of oxidation reactions: hydroxylation, dehydrogenation, and sulfoxidation. IDO stereoselectively hydroxylated several hydrophobic aliphaticl-amino acids, as well asl-isoleucine, and produced (S)-3-hydroxy-l-allo-isoleucine, 4-hydroxy-l-leucine, (S)-4-hydroxy-l-norvaline, 4-hydroxy-l-norleucine, and 5-hydroxy-l-norleucine. The IDO reaction product ofl-isoleucine, (2S,3R,4S)-4-hydroxyisoleucine, was again reacted with IDO and dehydrogenated into (2S,3R)-2-amino-3-methyl-4-ketopentanoate, which is also a metabolite found inB. thuringiensis2e2. Interestingly, IDO catalyzed the sulfoxidation of some sulfur-containingl-amino acids and generatedl-methionine sulfoxide andl-ethionine sulfoxide. Consequently, the effective production of various modified amino acids would be possible using IDO as the biocatalyst.

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Biophysical characterization of the 117 amino acids long N-terminal segment of D-Raf (Isoform A)

10.31274/rtd-180813-16211 ◽

2007 ◽

Author(s):

Oren Tchaicheeyan

Keyword(s):

Amino Acids ◽

Terminal Segment ◽

Biophysical Characterization

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Post-proline endopeptidase, further characterization of the enzyme from pig kidneys

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19841846 ◽

1984 ◽

Vol 49 (8) ◽

pp. 1846-1853 ◽

Cited By ~ 4

Author(s):

Karel Hauzer ◽

Tomislav Barth ◽

Linda Servítová ◽

Karel Jošt

Keyword(s):

Amino Acids ◽

Aspartic Acid ◽

Ion Exchange Chromatography ◽

Exchange Chromatography ◽

Relative Molecular Mass ◽

Enzyme Molecule ◽

Thiol Compounds ◽

Modified Method ◽

N Terminus

A post-proline endopeptidase (EC 3.4.21.26) was isolated from pig kidneys using a modified method described earlier. The enzyme was further purified by ion exchange chromatography on DEAE-Sephacel. The final product contained about 95% of post-proline endopeptidase. The enzyme molecule consisted of one peptide chain with a relative molecular mass of 65 600 to 70 000, containing a large proportion of acidic and alifatic amino acids (glutamic acid, aspartic acid and leucine) and the N-terminus was formed by aspartic acid or asparagine. In order to prevent losses of enzyme activity, thiol compounds has to be added.

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Characterization of UV-screening compounds, mycosporine-like amino acids, and scytonemin in the cyanobacteriumLyngbyasp. CU2555

FEMS Microbiology Ecology ◽

10.1111/1574-6941.12220 ◽

2013 ◽

Vol 87 (1) ◽

pp. 244-256 ◽

Cited By ~ 62

Author(s):

Rajesh P. Rastogi ◽

Aran Incharoensakdi

Keyword(s):

Amino Acids

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Avoided motifs: short amino acid strings missing from protein datasets

Biological Chemistry ◽

10.1515/hsz-2020-0383 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Pablo Mier ◽

Miguel A. Andrade-Navarro

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Protein Function ◽

Large Protein ◽

New Approach ◽

Cellular Context ◽

Human Proteins ◽

Context Specific ◽

Protein Datasets

Abstract According to the amino acid composition of natural proteins, it could be expected that all possible sequences of three or four amino acids will occur at least once in large protein datasets purely by chance. However, in some species or cellular context, specific short amino acid motifs are missing due to unknown reasons. We describe these as Avoided Motifs, short amino acid combinations missing from biological sequences. Here we identify 209 human and 154 bacterial Avoided Motifs of length four amino acids, and discuss their possible functionality according to their presence in other species. Furthermore, we determine two Avoided Motifs of length three amino acids in human proteins specifically located in the cytoplasm, and two more in secreted proteins. Our results support the hypothesis that the characterization of Avoided Motifs in particular contexts can provide us with information about functional motifs, pointing to a new approach in the use of molecular sequences for the discovery of protein function.

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Genetic and Molecular Characterization of sting, a Gene Involved in Crystal Formation and Meiotic Drive in the Male Germ Line of Drosophila melanogaster

Genetics ◽

10.1093/genetics/151.2.749 ◽

1999 ◽

Vol 151 (2) ◽

pp. 749-760 ◽

Cited By ~ 2

Author(s):

Armin Schmidt ◽

Gioacchino Palumbo ◽

Maria P Bozzetti ◽

Patrizia Tritto ◽

Sergio Pimpinelli ◽

...

Keyword(s):

Amino Acids ◽

Drosophila Melanogaster ◽

Null Allele ◽

Germ Line ◽

Meiotic Drive ◽

P Element ◽

Crystal Formation ◽

Male Sterile ◽

Male Sterile Mutation

Abstract The sting mutation, caused by a P element inserted into polytene region 32D, was isolated by a screen for male sterile insertions in Drosophila melanogaster. This sterility is correlated with the presence of crystals in spermatocytes and spermatids that are structurally indistinguishable from those produced in males carrying a deficiency of the Y-linked crystal (cry) locus. In addition, their morphology is needle-like in Ste+ flies and star-shaped in Ste flies, once again as observed in cry– males. The sti mutation leads to meiotic drive of the sex chromosomes, and the strength of the phenomenon is correlated with the copy number of the repetitive Ste locus. The same correlation is also true for the penetrance of the male sterile mutation. A presumptive sti null allele results in male sterility and lethal maternal effect. The gene was cloned and shown to code for a putative protein that is 866 amino acids long. A C-terminal domain of 82 amino acids is identified that is well conserved in proteins from different organisms. The gene is expressed only in the germline of both sexes. The interaction of sting with the Ste locus can also be demonstrated at the molecular level. While an unprocessed 8-kb Ste primary transcript is expressed in wild-type males, in X/Y homozygous sti males, as in X/Y cry– males, a 0.7-kb mRNA is produced.

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