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J H Hash

Publications and source records attributed to J H Hash.

At least 19 recordsLinked to original sources
PubMed1990

Preliminary crystallographic examination of a novel fungal lysozyme from Chalaropsis.

The lysozyme from the fungus of the Chalaropsis species has been crystallized. This lysozyme (Mr 22,415) displays no sequence homology with avian, phage, or mammalian lysozymes, however, preliminary studies indicate significant sequence homology with the bacterial lysozyme from Streptomyces. Both enzymes are unusual in possessing beta-1,4-N-acetylmuramidase and beta-1,4-N,6-O-diacetylmuramidase activity. The crystals grow from solutions of ammonium sulfate during growth periods from several months to a year. The space group is P2(1)2(1)2(1) with a = 34.0 A, b = 42.6 A, c = 122.1 A. Preliminary data indicate that there is 1 molecule/asymmetric unit. A complete native data set has been collected to 2.57-A resolution. The crystals are highly ordered and exhibit diffraction patterns to d-spacings less than 1.5 A.

Crystallization↗
PubMed1983

The repeating sequence of the capsular polysaccharide of Staphylococcus aureus M.

The anomeric configuration of the sugar residues of the capsular polysaccharide antigen of Staphylococcus aureus M were established by 13C-n.m.r. spectroscopy, and the linkage positions by g.l.c.-m.s. after methylation, indicating a leads to 4)-O-(2-acetamido-2-deoxy-alpha-D-galactopyranosyluronic acid)-(1 leads to 4)-O-(2-acetamido-2-deoxy-alpha-D-galactopyranosyluronic acid)-(1 leads to 3)-O-(2-acetamido-2-deoxy-alpha-D-fucopyranosyl)-(1 leads to repeating unit. A taurine residue is linked by an amide bond, on the average, to every fourth 2-acetamido-2-deoxy-D-galactopyranosyluronic acid residue.

Amino Acids↗
PubMed1982

A review of the molecular structure of tetanus toxin.

A discontinuous preparative polyacrylamide gel electrophoresis system has been developed and used to purify both the nicked and unnicked forms of tetanus toxin. The system was also used to prepare purified H and L chain peptides from the nicked toxin. The results show that the endogenous protease(s), which convert unnicked toxin to the nicked form, produce multiple species of nicked toxin, and heterogeneity in the H and L chains. The major amino termini of the toxins and their peptide components are: extract toxin, proline; filtrate toxin, proline, serine and asparagine; L chain, proline; and H chain, serine and asparagine. The L chain is located in the amino terminal position of the toxin molecule and the H chain the carboxy terminal end. A model is proposed to explain these results. Using the analytical ultracentrifuge, we have determined the molecular weights of extract and filtrate toxins to be 140000 +/- 5000 and 128000 +/- 3000, respectively. Using SDS-polyacrylamide gel electrophoresis we estimate the molecular weights of the H and L chains to be 87000 and 48000 daltons, respectively. Circular dichroic spectra of the toxins and their peptide components indicate that: the major tryptophanyl band in the toxin is contributed almost entirely by the H chain, the microenvironments of all the aromatics and disulfides in the two toxins appear to have small if any differences, the two toxins show little difference in their ordered secondary structure, and the two peptides when separated from one another still retain 80% of the helical structure that is present in the intact toxin but show a considerable loss of beta-structure. The crystalline form of the nicked toxin has a hexagonal symmetry with two dimensional reciprocal lattice constants of 1/150 A-1 and 1/150 A-1. The crystals appear to belong to the two dimensional plane group P6 suggesting that each unit cell contains 6 or a multiple of 6 toxin molecules.

Amino Acids↗
PubMed1982

Conformational and molecular weight studies of tetanus toxin and its major peptides.

Two forms of tetanus toxin have been purified from Clostridium tetani cultures. These forms, obtained from filtrate and cellular extracts, were characterized by analytical ultracentrifugation using both conventional and meniscus-depletion sedimentation equilibrium. The molecular weight of filtrate toxin was found to be 128,000 +/- 3,000, while the extract toxin, which tended to self-associate, appeared somewhat larger, 140,000 +/- 5,000. The heavy and light chains were prepared from filtrate toxin, and their molecular weights were estimated to be 87,000 and 48,000, respectively, using polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The circular dichroic spectra of the extract and filtrate toxins are quite similar between 200-300 nm indicating that no major conformational difference exists between the two. The toxins contain both alpha-helicity and beta-structure. Interestingly, the isolated chains contain appreciable helicity (e.g., the sum of the chain helicities is over 80% of that found in filtrate toxin), but they appear to have relatively low contents of beta-structure. The sum of the spectra of the chains in both the near- and far-ultraviolet does not yield that found for filtrate toxin, although the similarity is far more striking than the difference. The prominent 293.5 nm negative circular dichroic band of tetanus toxin can be assigned to tryptophanyl residues almost exclusively in the heavy chain. The similarity in the magnitude of this band in the separated chain and toxin suggests that the microenvironments of the contributing tryptophans change very little when toxin is dissociated into its constituent chains.

Circular Dichroism↗
PubMed1981

Lack of distant relationship between lysozyme Ch and hen egg white lysozyme: computer comparison studies.

A computer search, made for distant relationships between lysozyme Ch, hen egg white lysozyme, and bacteriophage T4 lysozyme, revealed no unusual similarities in their amino acid sequences. Also, antibodies generated against lysozyme Ch failed to cross react with hen egg white lysozyme and vice versa. These lysozymes most likely represent examples of convergent evolution.

Amino Acid Sequence↗
PubMed1978

Enzymatic fragmentation of tetanus toxin. Identification and characterization of an atoxic, immunogenic fragment.

Purified filtrate tetanus toxin was subjected to limited digestion with papain and the resulting fragments were separated by gel exclusion chromatography and characterized. One atoxic fragment was shown to react with antiserum against tetanus toxoid and was capable of inducing antibodies in rabbits that neutralized native tetanus toxin, The fragment had an estimated molecular weight of 56,000 by SDS polyacrylamide gel electrophoresis and 62,000 by sedimentation equilibrium. In the presence of a reducing agent, the fragment yielded two components with approximatec molecular weights of 23,000 and 32,000. Thus, it appears that the atoxic, immunogenic fragment is composed of two peptides joined by at least one disulfide bond. The fragment was examined by circular dichroism and data analysis indicated the presence of considerable beta-structure, but little, if any, alpha-helicity. This is significantly different from the estimates for filtrate toxin. 29% alpha-helicity and 23% beta-structure. Above 250 nm, the circular dichroic spectrum of the fragment was also distinct from that of intact toxin.

Amino Acids↗
PubMed1977

Structural analysis of the surface polysaccharide of Staphylococcus aureus M.

The chemical structure of the surface polysaccharide from Staphylococcus aureus M was investigated by a combination of methanolytic, hydrolytic, and chromatographic techniques. The repeating unit that was most consistent with the data was a hexasaccharide composed of N-acetyl-D-aminogalacturonic acid, N-acetyl-D-fucosamine, and taurine in molar ratios of 4:2:1. A disaccharide was isolated and characterized, by combined gas-liquid chromatography-mass spectrometry, as N-acetyl-D-aminogalacturonyl-(1 leads to 3)-N-acetyl-D-fucosamine. Taurine is linked to a carboxyl group of N-acetyl-D-aminogalacturonic acid via an amide bond.

Amino Acids↗
PubMed1975

The N, O-diacetylmuramidase of chalaropsis species. IV. Tryptic peptides.

Lysozyme Ch was hydrolyzed with trypsin in 2 M urea and the resulting peptides were separated by a combination of gel filtration and ion exchange chromatography. Ten peptides and free lysine were produced by tryptic action. The enzyme has 5 arginine and 4 lysine residues per molecule and one of the peptides arose from a chymotryptic-like cleavage of a tyrosyl-seryl bond near the amino-terminal end of the enzyme. The entire molecule is accounted for by the tryptic peptides, which have been ordered withing the peptides obtained by cyanogen bromide cleavage of the molecule.

Acetates↗
PubMed1975

The N, O-diacetylmuramidase of Chalaropsis species. V. The complete amino acid sequence.

The complete amino acid sequence of lysozyme Ch has been established by a combination of automated and manual Edman degradation and carboxypeptidase digestion.(see article)There is a single disulfide bond in the center of the molecule. The enzyme has 211 residues with a calculated molecular weight of 22,415. Lysozyme Ch has an amino acid sequence that is totally different from all other lysozymes whose sequences are known.

Acetates↗
PubMed1974

Biological properties of the encapsulated Staphylococcus aureus M.

Strain M, classified as a Staphylococcus aureus, behaves like the other rare encapsulated staphylococcal strains. It was clumping-factor negative, grew in diffuse-type colonies in serum-soft agar, and produced rapidly fatal disease in mice. Strain M was highly resistant to phagocytosis by human or mouse leukocytes and required both specific antibody and heat-labile serum factor(s) for efficient ingestion by human polymorphonuclear leukocytes. Electron micrographs confirmed the presence of a large capsule. Agglutination studies, active or passive mouse protection experiments, and opsonic studies revealed that strain M represents a new, immunologically distinct strain of encapsulated staphylococcus. Strain M differs from other known encapsulated staphylococci in several other respects: its cellular and colonial morphology is atypical; its LD(50) in the mouse peritoneal model is 100 times less than that of other mouse lethal strains; it is poorly opsonized by normal human serum; and, finally, it possesses an unusually large capsule as seen in electron micrographs.

Agglutination Tests↗