scholarly journals Two distinct secretory ribonucleases from human cerebrum: purification, characterization and relationships to other ribonucleases

1993 ◽  
Vol 296 (3) ◽  
pp. 617-625 ◽  
Author(s):  
T Yasuda ◽  
D Nadano ◽  
H Takeshita ◽  
K Kishi
Keyword(s):  
Amino Acid ◽  
Catalytic Properties ◽  
Pancreatic Enzyme ◽  
Total Activity ◽  
Inhibitory Effect ◽  
Amino Acid Sequences ◽  
Homogeneous State ◽  
Before And After ◽  
Molecular Masses ◽  
Terminal Amino

Two RNAases from human cerebrum were purified to an electrophoretically homogeneous state and their molecular masses were 22.0 kDa (tentatively called RNAase HB-1) and 19.0 kDa (RNAase HB-2). Analyses of the amino acid compositions, N-terminal amino acid sequences and catalytic properties of these enzymes provided strong evidence that they were strictly related to the secretory (sec) RNAases, such as the pancreatic enzyme, very similar immunologically to urinary sec RNAase, but clearly distinguishable from urinary non-secretory (nonsec) RNAase. There were several differences between HB-1 and HB-2, namely their immunological reactivities with specific antibodies, heat-stabilities, attached carbohydrate moieties and molecular masses. In particular, HB-2 appeared to be nonglycosylated, in view of its lack of affinity for several conjugated lectins, the absence of hexosamine and no change in electrophoretic mobility before and after peptide:N-glycosidase F digestion, whereas HB-1 and human sec RNAases purified from kidney, pancreas and urine all appeared to be glycosylated, as they moved to the same position as HB-2 when electrophoresed after glycosidase digestion. An antibody against urinary sec RNAase inhibited 75% and 20% of the total activity of the crude cerebral extract against RNA at pH 8.0 and 6.0 respectively, whereas an antibody against urinary nonsec RNAase had no such inhibitory effect. These findings suggest that yet another type(s) of cerebral RNAase, which is unable to cross-react immunologically with sec and nonsec RNAases, may exist. Two RNAases corresponding to HB-1 and HB-2 were identified in fresh cerebrospinal fluid.

scholarly journals Similarities and Specificities of Fungal Keratinolytic Proteases: Comparison of Keratinases of Paecilomyces marquandii and Doratomyces microsporus to Some Known Proteases

2005 ◽  
Vol 71 (7) ◽  
pp. 3420-3426 ◽  
Author(s):  
Helena Gradišar ◽  
Jožica Friedrich ◽  
Igor Križaj ◽  
Roman Jerala
Keyword(s):  
Amino Acid ◽  
Catalytic Efficiency ◽  
Kinetic Studies ◽  
Amino Acid Sequences ◽  
Proteinase K ◽  
Amino Acid Residues ◽  
Paecilomyces Marquandii ◽  
Molecular Masses ◽  
Terminal Amino ◽  
Hydrolysis Of

ABSTRACT Based on previous screening for keratinolytic nonpathogenic fungi, Paecilomyces marquandii and Doratomyces microsporus were selected for production of potent keratinases. The enzymes were purified and their main biochemical characteristics were determined (molecular masses, optimal temperature and pH for keratinolytic activity, N-terminal amino acid sequences). Studies of substrate specificity revealed that skin constituents, such as the stratum corneum, and appendages such as nail but not hair, feather, and wool were efficiently hydrolyzed by the P. marquandii keratinase and about 40% less by the D. microsporus keratinase. Hydrolysis of keratin could be increased by the presence of reducing agents. The catalytic properties of the keratinases were studied and compared to those of some known commercial proteases. The profile of the oxidized insulin B-chain digestion revealed that both keratinases, like proteinase K but not subtilisin, trypsin, or elastase, possess broad cleavage specificity with a preference for aromatic and nonpolar amino acid residues at the P-1 position. Kinetic studies were performed on a synthetic substrate, succinyl-Ala-Ala-Pro-Phe-p-nitroanilide. The keratinase of P. marquandii exhibited the lowest Km among microbial keratinases reported in the literature, and its catalytic efficiency was high in comparison to that of D. microsporus keratinase and proteinase K. All three keratinolytic enzymes, the keratinases of P. marquandii and D. microsporus as well as proteinase K, were significantly more active on keratin than subtilisin, trypsin, elastase, chymotrypsin, or collagenase.

scholarly journals Roles of the C-Terminal Amino Acids of Non-Hexameric Helicases: Insights from Escherichia coli UvrD

2021 ◽  
Vol 22 (3) ◽  
pp. 1018
Author(s):  
Hiroaki Yokota
Keyword(s):  
Escherichia Coli ◽  
Amino Acids ◽  
Amino Acid ◽  
Single Molecule ◽  
Underlying Mechanism ◽  
Amino Acid Sequences ◽  
E Coli ◽  
X Ray Crystallography ◽  
Terminal Amino

Helicases are nucleic acid-unwinding enzymes that are involved in the maintenance of genome integrity. Several parts of the amino acid sequences of helicases are very similar, and these quite well-conserved amino acid sequences are termed “helicase motifs”. Previous studies by X-ray crystallography and single-molecule measurements have suggested a common underlying mechanism for their function. These studies indicate the role of the helicase motifs in unwinding nucleic acids. In contrast, the sequence and length of the C-terminal amino acids of helicases are highly variable. In this paper, I review past and recent studies that proposed helicase mechanisms and studies that investigated the roles of the C-terminal amino acids on helicase and dimerization activities, primarily on the non-hexermeric Escherichia coli (E. coli) UvrD helicase. Then, I center on my recent study of single-molecule direct visualization of a UvrD mutant lacking the C-terminal 40 amino acids (UvrDΔ40C) used in studies proposing the monomer helicase model. The study demonstrated that multiple UvrDΔ40C molecules jointly participated in DNA unwinding, presumably by forming an oligomer. Thus, the single-molecule observation addressed how the C-terminal amino acids affect the number of helicases bound to DNA, oligomerization, and unwinding activity, which can be applied to other helicases.

scholarly journals Factor D̄ of the alternative pathway of human complement. Purification, alignment and N-terminal amino acid sequences of the major cyanogen bromide fragments, and localization of the serine residue at the active site

1980 ◽  
Vol 187 (3) ◽  
pp. 863-874 ◽  
Author(s):  
D M Johnson ◽  
J Gagnon ◽  
K B Reid
Keyword(s):  
Amino Acid ◽  
Sequence Analysis ◽  
Amino Acid Sequence ◽  
Alternative Pathway ◽  
Amino Acid Sequences ◽  
Serine Residue ◽  
Amino Acid Sequence Analysis ◽  
Terminal Amino Acid ◽  
Terminal Amino ◽  
Terminal Amino Acid Sequence

The serine esterase factor D of the complement system was purified from outdated human plasma with a yield of 20% of the initial haemolytic activity found in serum. This represented an approx. 60 000-fold purification. The final product was homogeneous as judged by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis (with an apparent mol.wt. of 24 000), its migration as a single component in a variety of fractionation procedures based on size and charge, and its N-terminal amino-acid-sequence analysis. The N-terminal amino acid sequence of the first 36 residues of the intact molecule was found to be homologous with the N-terminal amino acid sequences of the catalytic chains of other serine esterases. Factor D showed an especially strong homology (greater than 60% identity) with rat ‘group-specific protease’ [Woodbury, Katunuma, Kobayashi, Titani, & Neurath (1978) Biochemistry 17, 811-819] over the first 16 amino acid residues. This similarity is of interest since it is considered that both enzymes may be synthesized in their active, rather than zymogen, forms. The three major CNBr fragments of factor D, which had apparent mol.wts. of 15 800, 6600 and 1700, were purified and then aligned by N-terminal amino acid sequence analysis and amino acid analysis. By using factor D labelled with di-[1,3-14C]isopropylphosphofluoridate it was shown that the CNBr fragment of apparent mol.wt. 6600, which is located in the C-terminal region of factor D, contained the active serine residue. The amino acid sequence around this residue was determined.

Comparative analyses of Serratia spp. outer membrane porin proteins

1993 ◽  
Vol 39 (4) ◽  
pp. 442-447 ◽  
Author(s):  
Joanne Hutsul ◽  
Elizabeth Worobec ◽  
Tom R. Parr Jr. ◽  
Gerald W. Becker
Keyword(s):  
Amino Acid ◽  
Serratia Marcescens ◽  
Single Channel ◽  
Enteric Bacteria ◽  
Amino Acid Sequences ◽  
Chromosomal Dna ◽  
Terminal Amino Acid ◽  
Molecular Weight Range ◽  
Terminal Amino ◽  
Porin Proteins

Eight Serratia strains and several members of the Enterobacteriaceae family were used in immunoblot and Southern DNA hybridization experiments and probed with antibody and DNA probes specific for the 41-kDa Serratia marcescens porin, to determine the extent of homology between Gram-negative porins. Immunoblot analyses performed using porin-specific rabbit sera and cell envelope preparations from these strains revealed that all strains produced at least one cross-reactive protein in the 41-kDa molecular weight range. Chromosomal DNA from each of the same strains was used in Southern analyses, probed with a 20-base-length oligonucleotide probe deduced from the N-terminal amino acid sequence of the 41-kDa Serratia marcescens porin. The probe hybridized to DNA from all of the Serratia species and six of the nine other enteric bacteria. Putative porin proteins from all the Serratia species were subjected to N-terminal amino acid sequencing and porin functional analysis using the black lipid bilayer method. All amino acid sequences were identical, with one exception in which an asparagine was substituted for an aspartic acid in Serratia rubidaea. All porins had very similar porin function (single channel conductance ranging between 1.72 and 2.00 nS). The results from this study revealed that a strong conservation exists among the Serratia porins and those produced by other enteric bacteria.Key words: porins, Serratia marcescens, homology studies.

Neisseria pili proteins: amino-terminal amino acid sequences and identification of an unusual amino acid

Biochemistry ◽  
1978 ◽  
Vol 17 (3) ◽  
pp. 442-445 ◽  
Author(s):  
Mark A. Hermodson ◽  
Kirk C. S. Chen ◽  
Thomas M. Buchanan
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequences ◽  
Terminal Amino Acid ◽  
Amino Terminal ◽  
Terminal Amino ◽  
Unusual Amino Acid

scholarly journals Protein-sequence studies on Rh-related polypeptides suggest the presence of at least two groups of proteins which associate in the human red-cell membrane

1988 ◽  
Vol 256 (3) ◽  
pp. 1043-1046 ◽  
Author(s):  
N D Avent ◽  
K Ridgwell ◽  
W J Mawby ◽  
M J Tanner ◽  
D J Anstee ◽  
...  
Keyword(s):  
Amino Acid ◽  
Blood Group ◽  
Protein Sequence ◽  
Amino Acid Sequences ◽  
Red Cells ◽  
British Library ◽  
Blood Group System ◽  
Terminal Amino Acid ◽  
Red Cell Membrane ◽  
Terminal Amino

The Rh D blood-group antigen forms part of a complex, involving several other polypeptides, that is deficient in the red cells of individuals who lack all the antigens of the Rh blood-group system (Rhnull red cells). These include components recognized by anti-(Rh D) antibodies and the murine monoclonal antibodies R6A and BRIC 125. We have carried out protein-sequence studies on the components immunoprecipitated by these antibodies. Anti-(Rh D) antibodies immunoprecipitate an Mr-30,000-32,000 polypeptide (the D30 polypeptide) and an Mr-45,000-100,000 glycoprotein (D50 polypeptide). Antibody R6A immunoprecipitates two glycoproteins of Mr 31,000-34,000 (R6A32 polypeptide) and Mr 35,000-52,000 (R6A45 polypeptide). The D30 and R6A32 polypeptides were found to have the same N-terminal amino acid sequences, showing that they are closely related proteins. The D50 polypeptide and the R6A45 polypeptide also had indistinguishable N-terminal amino acid sequences that differed from that of the D30 and R6A32 polypeptides. The putative N-terminal membrane-spanning segments of the two groups of proteins showed homology in their amino acid sequence, which may account for the association of each of the pairs of proteins during co-precipitation by the antibodies. Supplementary data related to the protein sequence have been deposited as Supplementary Publication SUP 50417 (6 pages) at the British Library Document Supply Centre, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1988) 249, 5.

scholarly journals Molecular Identification of Family 38 α-Mannosidase of Bacillus sp. Strain GL1, Responsible for Complete Depolymerization of Xanthan

2002 ◽  
Vol 68 (6) ◽  
pp. 2731-2736 ◽  
Author(s):  
Hirokazu Nankai ◽  
Wataru Hashimoto ◽  
Kousaku Murata
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Cell Extract ◽  
Amino Acid Sequences ◽  
Glycoside Hydrolase Family ◽  
Sequence Information ◽  
Reading Frame ◽  
A Cell ◽  
Terminal Amino ◽  
Amino Acid Sequence Information

ABSTRACT When cells of Bacillus sp. strain GL1 were grown in a medium containing xanthan as a carbon source, α-mannosidase exhibiting activity toward p-nitrophenyl-α-d-mannopyranoside (pNP-α-d-Man) was produced intracellularly. The 350-kDa α-mannosidase purified from a cell extract of the bacterium was a trimer comprising three identical subunits, each with a molecular mass of 110 kDa. The enzyme hydrolyzed pNP-α-d-Man (Km = 0.49 mM) and d-mannosyl-(α-1,3)-d-glucose most efficiently at pH 7.5 to 9.0, indicating that the enzyme catalyzes the last step of the xanthan depolymerization pathway of Bacillus sp. strain GL1. The gene for α-mannosidase cloned most by using N-terminal amino acid sequence information contained an open reading frame (3,144 bp) capable of coding for a polypeptide with a molecular weight of 119,239. The deduced amino acid sequence showed homology with the amino acid sequences of α-mannosidases belonging to glycoside hydrolase family 38.

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