Incorporation d'analogues structuraux d'aminoacides dans les protéines bactériennes au cours de leur synthèse in vivo

Munier, R. L.; Cohen, Georges N.

doi:10.1016/0006-3002(59)90011-3

Cited by 174 publications

(52 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Many amino acid antagonists act by being incorporated into proteins in place of their corresponding amino acid with the result that inactive proteins are formed (7,10). This mode of action seemed uinlikely for hydroxyproline in light of the evidence obtained from both plant (9) and animal systems (13) fig 1).…”

mentioning

confidence: 99%

Inhibition of Cell Elongation in Avena Coleoptile by Hydroxyproline

Cleland¹

1967

Plant Physiol.

View full text Add to dashboard Cite

Summiiiiary. A sttudy has been -made of the hydroxyproline-induiced inhibition of elongation of Avena coleoptile tissues. The isomers of 4-hydroxyproline differ in their effectiveness; only the L isomers iare growth inhibitors with the cis form (allohydroxyproline) being more effective than the trans form (hydroxyproline).Hydroxyproline differs from other amino acid antagonists and protein synthesis inhibitors in respect to 2 characteristics of the growth inhibition. First, a certain increment of auxin-induced elongation must take place following addition of hydroxyproline before the growth is inhibited. In contrast, pretreatment with other amino acid antagonists or protein synthesis inhibitors completely eliminates the ability of Avena coleoptile sections to respond to auxin. Secondly, sucrose markedly increases the magnitude of the hydroxyproline inhibition; i.e., sucrose acts to inhibit rather than promote growth when in the presence of hydroxyproline.It appears that hydroxyproline is a specific inhibitor for the synthesis of some factor which is utilized in elongation. Following addition of hydroxyprolline, auxininduced elongation contintues until the pool of this factor is exhausted; then elongation is inhibited.Auxiin-iniduiced growth can be inhibited by a wide variety of agents (3). One group of inhibitors are the amino acid antagonists. Both division and elongation of plant cells are inhibited by antagonists such as ethionine (2, 12, 14), canavanine (1) and p-fluorophenylalanine (8).In 1958, Steward et al. (14) reported that the free amino acid hydroxyproline wotuld inhibit the growth of carrot callus tissues. Cleland extended this resuilt by showing that cell elongation in Avena coleoptile sections was also blocked by hydroxyproline (4). In both cases, hydroxyproline seemed to be acting as an antagonist of proline metabolism since the addition of proline completely reversed the hydroxyproline-indtuced inhibition.Many amino acid antagonists act by being incorporated into proteins in place of their corresponding amino acid with the result that inactive proteins are formed (7, 10). This mode of action seemed uinlikely for hydroxyproline in light of the evidence obtained from both plant (9) and animal systems (13) that free hydroxyproline is not incorporated into proteins. In order to determine the mode of action of hydroxyproline on cell elongation, an investigation of the effects of hydroxyproline on growth and metabolism has been uindertaken. This paper extends the earlier ob-I Surnorted by United States Public Health Service Granlt GM-12881. Materials and MethodsAzenaz seedlings were grown as detailed earlier (2). Sections 5 mm in length were cuit from the region 3 to 8 mm below the tip of 2.5 to 3.25 cm long coleoptiles. Grouips of 10 sections were placed in test tubes with 5 ml of soltution. The test tubes were rotated at 1 rpm on a Rollardruim and after the desired length of time, the sections were meastired with a microscope fitted with an eyepiece micrometer. All manipulations and incuibations we...

show abstract

mentioning

confidence: 99%

Inhibition of Cell Elongation in Avena Coleoptile by Hydroxyproline

Cleland¹

1967

Plant Physiol.

View full text Add to dashboard Cite

show abstract

“…Possibly, the alteration of phenylalanyl-tRNA synthetase per se causes resistance, since thereby PFP may not be efficiently activated to give rise to nonfunctional proteins (a major cause of PFP toxicity [26]). Thus our mutants could have altered charging activities for both Phe and PFP.…”

Section: Discussionmentioning

confidence: 99%

“…The technique used was that of Cohen et al. (7), except for transformation of the temperature-sensi- (26). Mutants resistant to PFP have been isolated with alterations in phenylalanyl-tRNA synthetase (13), general aromatic amino acid transport (4), feedback inhibition of the first enzyme of the aromatic pathway (3-deoxy-Darabinoheptulosonic acid 7-phosphate [DAHP] synthetase) (15), and regulation of the phenylalanine operon (15,17).…”

Section: Methodsmentioning

confidence: 99%

Defective regulation of the phenylalanine biosynthetic operon in mutants of the phenylalanyl-tRNA synthetase operon

Borg-Olivier¹,

Tarlinton²,

Brown³

1987

J Bacteriol

View full text Add to dashboard Cite

Among mutants of Escherichia coli resistant to p-fluorophenylalanine (PFP) were some with constitutive expression of the phenylalanine biosynthetic operon (the pheA operon). This operon is repressed in the wild type by phenylalanine. The mutation in three of these mutants mapped in the aroH-aroD region of the E. coli chromosome at 37 min. A plasmid bearing wild-type DNA from this region restored p-fluorophenylalanine sensitivity and wild-type repression of the pheA operon. Analysis of subclones of this plasmid and comparison of its restriction map with published maps indicated that the mutations affecting regulation of the pheA operon lie in the structural genes for phenylalanyl-tRNA synthetase, pheST, probably in pheS. Thus, the pheST operon has a role in the regulation of phenylalanine biosynthesis, the most likely being that wild-type phenylalanyltRNA synthetase maintains a sufficient intracellular cqncentration of Phe-tRNA"e for attenuation of the pheA operon in the presence of phenylalanine. A revised gene order for the 37-min region of the chromosome is reported. Read clockwise, the order is aroD, aroH, pheT, and pheS.

show abstract

“…To circumvent oxidation, methionine residues in the N-terminal peptide sequence were replaced by norleucine (Nle), which is common practice in organic peptide chemistry. [20][21][22][23] The complete synthesis of CysTACtin 9 was initiated with the removal of the Fmoc group of the Rink amide argogel resin (2), and treatment with the TAC scaffold (1) [1] by using BOP as a coupling reagent (Scheme 1). Solid phase peptide synthesis (SPPS) then afforded the sequence that mimicked the bhairpin loop of cystatin, which was subsequently acetylated to give 4.…”

Section: Design and Synthesis Of Cystatin Mimicsmentioning

confidence: 99%

Synthesis and Evaluation of TAC‐Based Inhibitors of Papain as Mimics of Cystatin B

et al. 2007

View full text Add to dashboard Cite

An approach for mimicking protein–protein interactions by using a discontinuous epitope to construct a mimic that is about one tenth of the size of a natural inhibitor of papain, namely, cystatin B, is described. The discontinuous epitope of cystatin B, which is involved in the interaction with papain, was mimicked by synthesis of a tripodal molecular construct by using the triazacyclophane (TAC) scaffold. The mimic contains three peptide arms: one that mimics the N terminus, one that mimics the C terminus, and one that mimics the β‐hairpin loop structure of cystatin B. These peptide sequences were assembled on the TAC scaffold. The resulting cystatin mimic, CysTACtin 9, showed excellent inhibition of papain with a Ki of 12 nM, which approaches the inhibitory potency of cystatin B (Ki=0.12 nM). Experiments with molecular constructs that contained one or two arms or a mixture of the nonscaffolded peptides showed that both scaffolding and the presence of the three peptide arms are crucial for a successful mimic.

show abstract

Incorporation d'analogues structuraux d'aminoacides dans les protéines bactériennes au cours de leur synthèse in vivo

Cited by 174 publications

References 17 publications

Inhibition of Cell Elongation in Avena Coleoptile by Hydroxyproline

Inhibition of Cell Elongation in Avena Coleoptile by Hydroxyproline

Defective regulation of the phenylalanine biosynthetic operon in mutants of the phenylalanyl-tRNA synthetase operon

Synthesis and Evaluation of TAC‐Based Inhibitors of Papain as Mimics of Cystatin B

Contact Info

Product

Resources

About