Fred C. Westall

Fifteen-minute acid hydrolysis of peptides.

Abstract During the last several years we have been using anaerobic and aerobic propionic acid/hydrochloric (HCl) hydrolysis as an analytical tool. Our previous communication (1) showed that not only free peptides but also peptides made by the Merrifield procedure (2–4) and still attached to the resin could be hydrolyzed quantitatively in 2 hr at 130°C. This procedure compared favorably (1) with constant boiling HCl hydrolysis which requires initial removal of the peptides from the resin and takes 24 hr. This publication compares the results of 55 peptides, 1 11 free and 44 attached to resin, hydrolyzed aerobically with propionic acid/hydrochloric acid for 15 min at 150°C, 15 min at 160°C, and 2 hr at 130°C.

Brain-derived fibroblast growth factor: A study of its inactivation

Brain fibroblast growth factor has been identified as a component of myelin basic protein. Its activity is destroyed when treated with a variety of solvents including dilute acid, organic solvents and solutions of guanidine hydrochloride. These conditions do not alter the encephalitogenic properties of myelin basic protein.

Serotonin binding sites I. structures of sites on myelin basic protein, LHRH, MSH, ACTH, interferon, serum albumin, ovalbumin and red pigment concentrating hormone

We report the results of nuclear magnetic resonance spectroscopy studies of combinations of serotonin (5-hydroxytryptamine) with the tryptophan peptide sequence and similar peptides from myelin basic protein. The binding site appears to consist of the sequence Arg Phe Ser Trp. Similar serotonin binding sites were found to exist on LHRH (Tyr Ser Trp) and MSH-ACTH tetrapeptide (Phe Arg Trp). These binding sites are specific to serotonin as is demonstrated by lack of binding by dopamine, histamine, acetylcholine and a dozen other pharmacologically active amines and indoles. Drugs known to affect serotonin levels, e.g., fenfluramine and L-DOPA, bind weakly to these sites. Structural and functional similarities between the tryptophan peptide, LHRH, and MSH-ACTH with an ACTH-like peptide of human leukocyte interferon, with human and bovine serum albumin, hen ovalbumin, and with red pigment concentrating hormone suggest that the latter peptides may also contain similar serotonin binding sites. The elucidation of serotonin binding sites on these peptides and proteins has implications for understanding various aspects of cancer, autoimmunity, neurological disease, and peptide hormone control.

An explanation of prevention and suppression of experimental allergic encephalomyelitis

An explanation of experimental allergic encephalomyelitis prevention and suppression is presented based upon evidence that the active unit in disease induction is an encephalitogen-adjuvant complex. The stereochemical complementarity in structure of the encephalitogen and adjuvant is mirrored in complementarity in the recognition sites of lymphocyte populations activated against encephalitogen and adjuvant. Since two complementary lymphocyte populations are necessary for disease induction, any procedure that prevents the development of one of these populations will prevent disease induction. Any procedure that eliminates one population after induction has occurred will suppress the disease. We argue that all extant data support the hypothesis. Several new experiments are proposed to further test it.

Bovine pineal antireproductive tripeptide binds to luteinizing hormone-releasing hormone: A model for peptide modulation by sequence specific peptide interactions?

We report results of chromatographic, pH titration and nuclear magnetic resonance (NMR) spectroscopy studies demonstrating that the bovine pineal antireproductive tripeptide, Thr-Ser-Lys (BPART), binds to luteinizing hormone-releasing hormone (LHRH) at a site comprised of LHRH 2-5 (His-Trp-Ser-Tyr). BPART and LHRH have been shown to be antagonists in vitro. The binding constant is ca. 2 X 10(3)/mole. An NMR study of fifty other peptide pairs demonstrates that the binding is sequence and residue specific. The binding provides evidence of the amino acid pairing hypothesis, and suggests the possibility of modulation of one peptide by directly binding with another peptide.

Released myelin basic protein: The immunogenic factor?

Abstract Calculations are given which indicate that possibly the destruction of myelin in EAA and conceivably in human disease, for example Multiple Sclerosis, is due to activated lymphocyte recognition of released soluble basic protein and not myelin associated protein. This released basic protein accumulates during the proteins normal which is probably initiated by non-enzymatic deamidation.

The Encephautogenic Dose Response in Guinea Pigs of the Tryptophan Region of Myelin Basic Protein

The encephalitogenic dose response for the synthetic tryptophan peptide from the basic protein of myelin is given. The best dose in guinea pigs for disease induction using the peptide is between 1 and 3ug. Using doses higher or lower induces EAE in fewer animals.

An encephalitogenic region for rabbits

Abstract A synthetic peptide containing residues 154–162 within the rabbit myelin basic protein has been found to be encephalitogenic in rabbits. Synthetic analogs of this region have also been tested for their disease-producing ability.

Encephalitogenic Regions for the Lewis Rat within the Myelin Basic Protein

The sequence, phe lys asn ile val thr pro arg thr pro pro pro ser gln gly lys gly arg gly leu ser ser arg phe ser trp gly ala glu gly gln isolated from the peptic digestion of guinea pig myelin basicprotein is able to produce EAE in Lewis rats. The synthetic peptide phe lys phe gly gly arg asp ser arg, an analog of residues 154-162, is encephalitogenic in Lewis rats when B. pertussis is used as the adjuvant.

Fenfluramine binds 5-hydroxytryptophan.

Fenfluramine, an anorexigenic drug, lowers serotonin (5-hydroxytryptamine) and 5-hydroxyindoleacetic acid levels in brain, spinal fluid, and blood, and has been used as a treatment for autism. Fenfluramines mode of action is unknown. We present evidence from chromatography and nuclear magnetic resonance spectroscopy that fenfluramine selectively binds the serotonin and 5-hydroxyindoleacetic acid precursor, 5-hydroxytryptophan. The mode of binding may have general applications for the understanding of drug activity, receptor binding, and for the design of specific antagonists to aromatic compounds.