Studies on Polypeptides and Amino Acids by Countercurrent Distribution

Lc, Craig; Jd, Gregory; Gt, Barry

doi:10.1101/sqb.1950.014.01.005

Cited by 30 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…By countercurrent distribution in the solvent system methanol-waterbenzene-chloroform (23:7:15:15) three fractions were obtained, the major fraction designated gramicidin A (distribution coefficient K = 0.61), and two minor fractions designated gramicidin B (K = 0.31) and gramicidin C (K = 1.32). [3][4][5] The structure of gramicidin A, a mixture of valine-(I) and isoleucine-gramicidin A (II),5'6 was recently elucidated7-9 and confirmed by synthesis. 10 Gramicidin B is composed of very similar acids except that one tryptophan is replaced by phenylalanine.…”

mentioning

confidence: 99%

Gramicidin. VII. The Structure of Valine- and Isoleucine-gramicidin B

Sarges¹,

Witkop²

1965

J. Am. Chem. Soc.

View full text Add to dashboard Cite

mentioning

confidence: 99%

Gramicidin. VII. The Structure of Valine- and Isoleucine-gramicidin B

Sarges¹,

Witkop²

1965

J. Am. Chem. Soc.

View full text Add to dashboard Cite

“…glycine, L-alanine, D-and L-valine, D-(and possibly L-) leucine, and L-tryptophan (Synge, 1949). In gramicidins B and C, L-phenylalanine and L-tyrosine, respectively, replace a part of the tryptophan residues (Craig, Gregory, and Barry, 1949).…”

mentioning

confidence: 99%

BIOSYNTHESIS OF GRAMICIDIN AND TYROCIDINE IN THE DUBOS STRAIN OF BACILLUS BREVIS I

1963

View full text Add to dashboard Cite

Biosynthesis of gramicidin and tyrocidine in the Dubos strain of Bacillus brevis. I. Experiments with growing cultures. J. Bacteriol. 85:329-338. 1963.-A simple chromatographic method was developed for the isolation of gramicidin and tyrocidine from tyrothricin of Bacillus brevis. A Tryptone-yeast extract-glucose medium containing mineral salts gave the best yields of peptides in a stationary culture of the organism. The incorporation of suitable C'4-labeled amino acids into gramicidin and tyrocidine was studied Several analogues of tyrocidine amino acids (,B-hydroxyglutamic acid, pipecolic acid, ,B-2thienylalanine, p-fluorophenylalanine, and phenyl glycine) selectively reduced tyrocidine synthesis, when added to the nutrient medium. At the same time, the production of gramicidin was augmented. Growth and protein synthesis were not affected. Two analogues in isotopic form, ,B-2thienylalanine and isoleucine, were shown to give rise to high degrees of labeling in tyrocidine. Radioactive amino acids. DL-Pipecohic acid-H3 was a previously described preparation (Winnick and Winnick, 1961); DL-f3 (2-thienyl) alanine-3-C'4 and glycine-1-C14 were obtained from the Commissariat A l'Energie Atomique, France. DL-Proline-l-C'4, DL-ornithine-2-C'4, DL-valine-1-C14, and ethanolamine-1,2-Cl4 were from the California Corporation for Biochemical Research. L-Isoleucine-U-Cl4 was purchased from the Radiochemical Centre, England. Amino acid analogues. DL-p-Fluorophenylalanine, phenylglycine, DL-pipecolic acid, and DL-f-2-thienylalanine were purchased from the California Corporation for Biochemical Research.

show abstract

“…Therefore the action of tyrothricin (gramicidin + tyrocidine) against Gram-positive bacteria mainly was attributed to gramicidin in the topical treatment of wounds infected with Gram-positive bacteria [39]. Later, gramicidin was described as a mixture of peptides and gramicidins A-C [40], which were sequenced in the 1960s [41][42][43]. Gramicidins are considered as the first antimicrobial peptides clinically tested [44], commercially manufactured, and with a known amino acid sequence [45].…”

Section: Discovery Of Native Amps: a Historical Overviewmentioning

confidence: 99%

Discovery, Optimization, and Clinical Application of Natural Antimicrobial Peptides

et al. 2021

View full text Add to dashboard Cite

Antimicrobial peptides (AMPs) are widespread in multicellular organisms. These structurally diverse molecules are produced as the first line of defense against pathogens such as bacteria, viruses, fungi, and parasites. Also known as host defense peptides in higher eukaryotic organisms, AMPs display immunomodulatory and anticancer activities. During the last 30 years, technological advances have boosted the research on antimicrobial peptides, which have also attracted great interest as an alternative to tackling the antimicrobial resistance scenario mainly provoked by some bacterial and fungal pathogens. However, the introduction of natural AMPs in clinical trials faces challenges such as proteolytic digestion, short half-lives, and cytotoxicity upon systemic and oral application. Therefore, some strategies have been implemented to improve the properties of AMPs aiming to be used as effective therapeutic agents. In the present review, we summarize the discovery path of AMPs, focusing on preclinical development, recent advances in chemical optimization and peptide delivery systems, and their introduction into the market.

show abstract

Studies on Polypeptides and Amino Acids by Countercurrent Distribution

Cited by 30 publications

References 0 publications

Gramicidin. VII. The Structure of Valine- and Isoleucine-gramicidin B

Gramicidin. VII. The Structure of Valine- and Isoleucine-gramicidin B

BIOSYNTHESIS OF GRAMICIDIN AND TYROCIDINE IN THE DUBOS STRAIN OF BACILLUS BREVIS I

Discovery, Optimization, and Clinical Application of Natural Antimicrobial Peptides

Contact Info

Product

Resources

About