The Friesner Herbarium (BUT) of Butler University

The Friesner Herbarium (BUT) of Butler University is a collection of over 100,000 specimens built from the personal herbarium of Ray C. Friesner. He and other botanists at Butler amassed one of the largest and most complete collections of Indiana plants. Active exchange from the 1920’s through the 1940’s increased the holdings of plants from other states. Although the collection does not contain many type specimens, it is rich in vouchers from floristic and ecological studies conducted in the first half of the 20th century and published in the scientific journal,Butler University Botanical Studies.     

Endopeptidase-24.11, a Cell-Surface Peptidace of Central Nervous System Neurons, Is Expressed by Schwann Cells in the Pig Peripheral Nervous System

Endopeptidase-24.11 is a 90-kDa surface glycoprotein with the ability to hydrolyze a variety of biologically active peptides. Interest in this enzyme is based on the consensus that it may play a role in the termination of peptide signals in the central nervous system. In the present study, we have investigated the distribution of endopeptidase-24.11 in two nerves of the peripheral nervous system of newborn pigs: the sciatic, composed of a mixture of myelinated and nonmyelinated axons, and cervical sympathetic trunk in which greater than 99% of the axons are nonmyelinated. The endopeptidase was monitored enzymatically, as well as by immunoblotting and immunocytochemistry using mono- and polyclonal anti-endopeptidase antibodies. Endopeptidase-24.11 was detected in both the sciatic nerve and the cervical sympathetic trunk. Membrane preparations from sciatic nerve hydrolyzed 125I-insulin B-chain, and more than 50% of the activity was inhibited by phosphoramidon with an IC50 concentration of 3.2 nM. Moreover, a 90-kDa polypeptide was detected by immunoblotting of sciatic nerve membranes. The type of cells expressing the endopeptidase was determined by immunohistochemistry. In teased nerve preparations, these cells were identified morphologically as myelin- and non-myelin-forming Schwann cells. Endopeptidase-24.11 was also expressed by cultured Schwann cells from sciatic nerve and cervical sympathetic trunk maintained for 3 h in vitro. The presence of endopeptidase-24.11 on the Schwann cell surface raises the possibility of a potential role for the enzyme in nerve development and/or regeneration.     

An aspartate deletion mutation defines a binding site of the multifunctional FhuA outer membrane receptor of Escherichia coli K-12.

The FhuA protein of the outer membrane serves as a receptor for phages T5, T1, and phi 80, for colicin M, for the antibiotic albomycin, and for ferrichrome and related siderophores. To identify protein regions important for the multiple FhuA activities, fhuA genes of spontaneous chromosomal mutants which expressed wild-type amounts of the FhuA protein were sequenced. A mutant which was partially T5 sensitive but impaired in all other functions was missing aspartate residue 348 of the mature protein as a result of a three-base deletion. This aspartate residue is part of the hydrophilic sequence Asp-Asp-Glu-Lys. Replacement by site-specific mutagenesis of each of the Asp residues by Tyr, of Glu by Val, and of Lys by Met reduced FhuA activity but less than the Asp deletion did. Ferrichrome inhibited binding of phage phi 80 and of colicin M to these mutants in an allele-specific manner. A completely resistant derivative of the Asp deletion mutant contained, in addition, a leucine-to-proline substitution at position 106 and eight changed bases, converting at positions 576 to 578 an Arg-Pro-Leu sequence to Ala-Arg-Cys. The latter mutations and the Leu-to-Pro replacement alone did not alter sensitivity to the phages but reduced sensitivity to colicin M and albomycin 10- to 1,000-fold. The proline replacements probably disturb FhuA conformation and, in concert with the Asp deletion, inactivate FhuA completely. It is concluded that the Asp deletion site defines a region of FhuA which directly participates in binding of all FhuA ligands. Growth promotion studies on iron-limited media revealed that certain siderophores of the hydroxamate type, such as butylferrichrome, ferrichrysin, and ferrirubin, are taken up not only via FhuA but also via the FhuE outer membrane receptor protein.     

Nucleotide sequences of the sfuA, sfuB, and sfuC genes of Serratia marcescens suggest a periplasmic-binding-protein-dependent iron transport mechanism.

The cloned sfu region of the Serratia marcescens chromosome confers the ability to grow on iron-limited media to an Escherichia coli K-12 strain that is unable to synthesize a siderophore. This DNA fragment was sequenced and found to contain three genes termed sfuA, sfuB, and sfuC, arranged and transcribed in that order. The sfuA gene encoded a periplasmic polypeptide with calculated molecular weights of 36,154 for the precursor and 33,490 for the mature protein. The sfuB gene product was a very hydrophobic protein with a molecular weight of 56,589. The sfuC gene was found to encode a rather polar but membrane-bound protein with a molecular weight of 36,671 which exhibited strong homology to consensus sequences of nucleotide-binding proteins. The number, structural characteristics, and locations of the SfuABC proteins were typical of a periplasmic-binding-protein-dependent transport mechanism. How Fe3+ is solubilized and taken up across the outer membrane remains an enigma.     

Temporal translational regulation of the protamine 1 gene during mouse spermatogenesis

Temporal translational control is an important mechanism of gene regulation during mouse spermatogenesis. Studies of the protamine 1 gene, one member of a class of translationally regulated genes, have shown that it is first transcribed post-meiotically in round spermatids, and that the mRNA is stored in an untranslatable form as an inactive ribonucleoprotein particle for up to 1 week before it is translated. The analysis of the expression of fusions between the protamine gene and reporter genes in transgenic mice has demonstrated that sequences mapping in the 3'-untranslated region of the protamine mRNA are sufficient to confer protamine-like translational regulation on the chimeric mRNAs. It is proposed that sequence-specific RNA-binding proteins interact with the protamine 3'-untranslated region and mediate the temporal translational control. Future progress at elucidating the mechanism of translational regulation will come from the identification of translational control factors and their study in vitro and in vivo.     

Effect of pH and butyrate concentration on the production of acetone and butanol by Clostridium acetobutylicum grown in continuous culture

Summary When Clostridium acetobutylicum was grown in continuous culture under glucose limitation at neutral pH and varying dilution rates the only fermentation products formed were acetate, butyrate, carbon dioxide and molecular hydrogen. The Y _glucose ^max and (Y _ATP ^max ) _gluc ^exp values were 48.3 and 23.8 dry weight/mol, respectively. Acetone and butanol were produced when the pH was decreased below 5.0 (optimum at pH 4.3). The addition of butyric acid (20 to 80 mM) to the medium with a pH of 4.3 resulted in a shift of the fermentation from acid, to solvent formation.A preliminary report of part of this work was presented at a symposium Trends in the Biology of Fermentations for Fuels and Chemicals held December 7–11, 1980, at Brookhaven National Laboratory, Upton, New York; Gottschalk and Bahl 1981     

A complete separation of dimethylaminoazobenzenesulphonyl-amino acids. Amino acid analysis with low nanogram amounts of polypeptide with dimethylaminoazobenzenesulphonyl chloride.

Triacylglycerol synthesis by glycogen-depleted hepatocytes from fed rats that have low glycerol 3-phosphate contents was stimulated by the addition of glycerol 3-phosphate precursors. Glucagon decreased triacylglycerol synthesis only when it also lowered glycerol 3-phosphate content. The hyperbolic-like relationship between glycerol 3-phosphate content and rates of triacylglycerol synthesis was identical in the absence or presence of glucagon, indicating that the glucagon effect on triacylglycerol synthesis was not mediated through changes in enzyme activities of the esterification pathway but through changes in cellular glycerol 3-phosphate content.     

Analysis of neonatally induced tolerance of H-2 alloantigens

There is a considerable amount of evidence, confirmed and extended by our studies, in favor of clonal deletion of alloantigen-reactive cells in neonatally induced transplantation tolerance. We have demonstrated in adult mice bearing long-standing skin allografts that lymphocytes specifically reactive with the tolerated H-2 alloantigens are undetectable by mixed lymphocyte and graftversus-host reactions, and in cell-mediated lympholysis. In addition, lymphoid cells capable of suppressing the reactivity of syngeneic normal lymphocytes in these assays similarly escape detection. Moreover, putative precursors of T cells specific for the tolerated antigens cannot be activated polyclonally with concanavalin A (Con A), nor can they be identified among thymocytes ofH-2-tolerant mice. Since the tolerant state can be adoptively transferred with lymphohematopoietic cells to adult, syngeneic mice, we infer that transplantation tolerance is maintained by an active process that achieves specific clonal deletion at an early stage in the ontogeny of alloreactive T lymphocytes.