BIOCHEMICAL CHARACTERIZATION OF ?-N-OXALYL-l-?,?-DIAMINOPROPIONIC ACID, THE LATHYRUS SATIVUS NEUROTOXIN AS AN EXCITANT AMINO ACID

1970 ◽  
Vol 17 (8) ◽  
pp. 1295-1298 ◽  
Author(s):  
P. S. Cheema ◽  
G. Padmanaban ◽  
P. S. Sarma
Keyword(s):  
Amino Acid ◽  
Biochemical Characterization ◽  
Lathyrus Sativus ◽  
Diaminopropionic Acid

Biochemical characterization of a glucoamylase from Saccharomycopsis fibuligera R64

Biologia ◽  
2011 ◽  
Vol 66 (1) ◽  
Author(s):  
Dessy Natalia ◽  
Keni Vidilaseris ◽  
Pasjan Satrimafitrah ◽  
Wangsa Ismaya ◽  
Purkan ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Amino Acid ◽  
Amino Acid Sequence Identity ◽  
Biochemical Characterization ◽  
Saccharomycopsis Fibuligera ◽  
Sequence Identity ◽  
Ic50 Value ◽  
High Amino Acid ◽  
Ph Range

AbstractGlucoamylase from the yeast Saccharomycopsis fibuligera R64 (GLL1) has successfully been purified and characterized. The molecular mass of the enzyme was 56,583 Da as determined by mass spectrometry. The purified enzyme demonstrated optimum activity in the pH range of 5.6–6.4 and at 50°C. The activity of the enzyme was inhibited by acarbose with the IC50 value of 5 μM. GLL1 shares high amino acid sequence identity with GLU1 and GLA1, which are Saccharomycopsis fibuligera glucoamylases from the strains HUT7212 and KZ, respectively. The properties of GLL1, however, resemble that of GLU1. The elucidation of the primary structure of GLL1 contributes to the explanation of this finding.

FIBRINOGEN BIRMINGHAM; A NEW CONGENITAL HETERODIMERIC DYSFIBRINOGENEMIA WITH DEFECTIVE FIBRINOPEPTIDE A RELEASE (Aα 16 Arg→His)

1987 ◽  
Author(s):  
K R Siebenlist ◽  
J T Prchal ◽  
M W Masesson
Keyword(s):  
Amino Acid ◽  
Amino Acid Analysis ◽  
Hplc Analysis ◽  
Biochemical Characterization ◽  
Clinical Manifestations ◽  
Severe Bleeding ◽  
Fibrinopeptide A ◽  
History Of ◽  
Bleeding Episodes

Aα 16 Arg→His substitutions are common forms of congenital dysfibrinogenemias. Clinical manifestations range from asymptomatic to moderate hemorrhagic tendencies. Biochemical characterization of one such heterozygotic individual (Fibrinogen Louisville, Galanakis, etal. Ann NY Acad Sci 408:644,1983) indicated that only homodimeric fibrinogen molecules (i.e., containing either normal or abnormal Aα chains) were present. We isolated fibrinogen from the plasma of a 23 year old patient with a history of easy bruising and several recent moderate to severe bleeding episodes. Coagulability with reptilase was 677 (65-70%; n=5) whereas with thrombin (Ha) it approached 100%, depending directly upon the time of incubation with enzyme. HPLC analysis of Ila-induced fibrinopeptide release demonstrated the presence of an abnormal A-peptide (A*), amounting to 50% of the total, which was released more slowly than the normal A-peptide (A). Amino acid analysis of A* demonstrated the absence of Arg and the presence of His. Carboxypeptidase digestion confirmed the structure of A* as Aα 16 Arg-→ His. The clot and the soluble clot liquor resulting from reptilase treatment were separated and each was then further treated with Ilato release A*. HPLC analysis indicated that 31% of the total A* present in the sample was associated with the reptilase clot and 697 remained in the clot liquor. This distribution of A* suggests that Fibrinogen Birmingham, unlike Fibrinogen Louisville, contains heterodimeric molecules that are incorporated into the reptilase clottable fraction. This finding is consistent with a process of random hepatic assembly of dimeric fibrinogen molecules in a heterozygotic individual.

scholarly journals Biochemical characterization of a second family of human Ia molecules, HLA-DS, equivalent to murine I-A subregion molecules.

1982 ◽  
Vol 156 (2) ◽  
pp. 550-566 ◽  
Author(s):  
S M Goyert ◽  
J E Shively ◽  
J Silver
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Amino Acid Sequence Identity ◽  
Biochemical Characterization ◽  
Amino Acid Sequence Homology ◽  
Molecular Weights ◽  
Hla Dr ◽  
D Region ◽  
Polypeptide Chains

In mice, two families of structurally distinct Ia molecules, one designated I-A and the other I-E, have been identified and characterized. The HLA-DR molecules represent one family of human Ia molecules equivalent to the murine I-E molecules on the basis of amino acid sequence homology. We describe the isolation and biochemical characterization of a second family of human Ia molecules, designated HLA-DS for second D-region locus, equivalent to the murine I-A molecules. The human HLA-DS molecules consist of two polypeptide chains, DS alpha (37,000 mol wt) and DS beta (29,000 mol wt), with 73% amino acid sequence identity to the murine I-A molecules. Furthermore, the HLA-DS molecules are closely linked genetically to HLA-DR molecules, a situation analogous to that observed in mice. The similarity in molecular weights of the DR and DS molecules might explain why others have failed to identify the latter in man.

scholarly journals Genetic and Biochemical Characterization of OXA-535, a Distantly Related OXA-48-Like β-Lactamase

2018 ◽  
Vol 62 (10) ◽  
Author(s):  
L. Dabos ◽  
A. B. Jousset ◽  
R. A. Bonnin ◽  
N. Fortineau ◽  
A. Zavala ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Sequence ◽  
Amino Acid Sequence Identity ◽  
Biochemical Characterization ◽  
Content Type ◽  
Sequence Identity

ABSTRACT OXA-535 is a chromosome-encoded carbapenemase of Shewanella bicestrii JAB-1 that shares only 91.3% amino acid sequence identity with OXA-48. Catalytic efficiencies are similar to those of OXA-48 for most β-lactams, except for ertapenem, where a 2,000-fold-higher efficiency was observed with OXA-535. OXA-535 and OXA-436, a plasmid-encoded variant of OXA-535 differing by three amino acids, form a novel cluster of distantly related OXA-48-like carbapenemases. Comparison of blaOXA-535 and blaOXA-436 genetic environments suggests that an ISCR1 may be responsible for blaOXA-436 gene mobilization from the chromosome of Shewanella spp. to plasmids.

Genetic and biochemical characterization of FRI-3, a novel variant of the Ambler class A carbapenemase FRI-1

2019 ◽  
Vol 74 (10) ◽  
pp. 2891-2894 ◽  
Author(s):  
Jennifer Schauer ◽  
Sören G Gatermann ◽  
Matthias Marschal ◽  
Niels Pfennigwerth
Keyword(s):  
Amino Acid ◽  
Biochemical Characterization ◽  
Amino Acid Identity ◽  
Class A ◽  
Carbapenem Resistant ◽  
New Variant ◽  
Novel Variant ◽  
Almost All ◽  
Phenotypic Tests

Abstract Objectives To characterize a new variant of the FRI class A carbapenemase isolated from an MDR clinical Enterobacter cloacae isolate. Methods A carbapenem-resistant E. cloacae was isolated from a rectal swab from a patient in an ICU in Southern Germany. Various phenotypic tests confirmed production of a putative class A carbapenemase. The new bla gene variant, blaFRI-3, and its genetic environment were characterized by WGS. Biochemical characterization was performed by heterologous expression in Escherichia coli TOP10 and by purification of the enzyme with subsequent determination of its kinetic parameters. Results PCR and sequencing carried out for different class A carbapenemase genes confirmed the presence of a novel variant of blaFRI-1. The novel variant was named FRI-3 and exhibited 91%, 96% and 92% amino acid identity to FRI-1, FRI-2 and FRI-4, respectively. E. coli TOP10 expressing blaFRI-3 showed increased resistance to almost all β-lactams. Comparing the catalytic behaviour of FRI-3 and FRI-1, it was shown that FRI-3 had the same substrate spectrum, but basically hydrolysed β-lactams less efficiently than FRI-1. WGS data revealed that blaFRI-3 was located on a 111 kb plasmid. Conclusions The biochemical characterization of FRI-3 illustrates that even a few differences in the amino acid sequence can lead to altered catalytic activities of β-lactamases belonging to the same family.

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