Enzymatic Properties and Nucleotide and Amino Acid Sequences of a Thermostable β-Agarase from the Novel Marine Isolate, JAMB-A94

2004 ◽  
Vol 68 (5) ◽  
pp. 1073-1081 ◽  
Author(s):  
Yukari OHTA ◽  
Yuichi NOGI ◽  
Masayuki MIYAZAKI ◽  
Zhijun LI ◽  
Yuji HATADA ◽  
...  
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequences ◽  
Enzymatic Properties ◽  
The Novel ◽  
Marine Isolate

A novel gene, MEL1, mapped to 1p36.3 is highly homologous to the MDS1/EVI1 gene and is transcriptionally activated in t(1;3)(p36;q21)-positive leukemia cells

Blood ◽  
2000 ◽  
Vol 96 (9) ◽  
pp. 3209-3214 ◽  
Author(s):  
Naomi Mochizuki ◽  
Seiichi Shimizu ◽  
Toshiro Nagasawa ◽  
Hideo Tanaka ◽  
Masafumi Taniwaki ◽  
...  
Keyword(s):  
Amino Acid ◽  
Transcriptional Activation ◽  
Zinc Finger Protein ◽  
Fetal Liver ◽  
Amino Acid Sequences ◽  
Leukemia Cells ◽  
The Novel ◽  
Amino Acid Residues ◽  
Novel Gene ◽  
Pr Domain

The reciprocal translocation t(1;3)(p36;q21) occurs in a subset of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), which is frequently characterized by trilineage dysplasia, in particular dysmegakaryocytopoiesis, and poor prognosis. Previously, the breakpoint cluster region (BCR) at 3q21 was identified within a 60-kilobase (kb) region centromeric to the BCR of 3q21q26 syndrome and that at 1p36.3 within a 90-kb region. In this study, genes were searched near the breakpoints at 1p36.3, and a novel gene was isolated that encoded a zinc finger protein with a PR domain, which is highly homologous to theMDS1/EVI1 gene. The novel gene, designated asMEL1(MDS1/EVI1-like gene 1), with 1257 amino acid residues is 64% similar in nucleotide and 63% similar in amino acid sequences to MDS1/EVI1 with the same domain structure. The MEL1 gene is expressed in leukemia cells with t(1;3) but not in other cell lines or bone marrow, spleen, and fetal liver, suggesting that MEL1 is specifically in the t(1;3)(p36;q21)-positive MDS/AML. On the basis of the positional relationship between the EVI1 and MEL1 genes in each translocation, it was suggested that both genes are transcriptionally activated by the translocation of the 3q21 region with the Ribophorin I gene. Because of the transcriptional activation of the EVI1 family genes in both t(1;3)(p36;q21)-positive MDS/AML and 3q21q26 syndrome, it is suggested that they share a common molecular mechanism for the leukemogenic transformation of the cells.

scholarly journals Phenotypic and Enzymatic Comparative Analysis of the Novel KPC Variant KPC-5 and Its Evolutionary Variants, KPC-2 and KPC-4

2008 ◽  
Vol 53 (2) ◽  
pp. 557-562 ◽  
Author(s):  
Daniel J. Wolter ◽  
Philip M. Kurpiel ◽  
Neil Woodford ◽  
Marie-France I. Palepou ◽  
Richard V. Goering ◽  
...  
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequences ◽  
Single Amino Acid ◽  
Upstream Region ◽  
The Novel ◽  
Carbapenem Resistant ◽  
Flanking Regions ◽  
Hydrolysis Of ◽  
Additional Amino Acid

ABSTRACT A novel Klebsiella pneumoniae carbapenemase (KPC) variant, designated bla KPC-5, was discovered in a carbapenem-resistant Pseudomonas aeruginosa clinical isolate from Puerto Rico. Characterization of the upstream region of bla KPC-5 showed significant differences from the flanking regions of other bla KPC variants. Comparison of amino acid sequences with those of other KPC enzymes revealed that KPC-5 was an intermediate between KPC-2 and KPC-4, differing from KPC-2 by a single amino acid substitution (Pro103→Arg), while KPC-4 contained Pro103→Arg plus an additional amino acid change (Val239→Gly). Transformation studies with an Escherichia coli recipient strain showed differences in the properties of the KPC variants. KPC-4 and KPC-5 both had pIs of 7.65, in contrast with the pI of 6.7 for KPC-2. KPC-2 transformants were less susceptible to the carbapenems than KPC-4 and KPC-5 transformants. These data correlated with higher rates of imipenem hydrolysis for KPC-2 than for KPC-4 and KPC-5. However, KPC-4 and KPC-5 transformants had higher ceftazidime MICs, and the enzymes from these transformants had slightly better hydrolysis of this drug than KPC-2. KPC-4 and KPC-5 were more sensitive than KPC-2 to inhibition by clavulanic acid in both susceptibility testing and hydrolysis assays. Thus, KPC enzymes may be evolving through stepwise mutations to alter their spectra of activity.

scholarly journals Two Highly Similar Chitinases from Marine Vibrio Species have Different Enzymatic Properties

Marine Drugs ◽  
2020 ◽  
Vol 18 (3) ◽  
pp. 139
Author(s):  
Xinxin He ◽  
Min Yu ◽  
Yanhong Wu ◽  
Lingman Ran ◽  
Weizhi Liu ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Extracellular Enzymes ◽  
Vibrio Harveyi ◽  
Amino Acid Sequences ◽  
Enzymatic Properties ◽  
Site Directed Mutagenesis ◽  
Amino Acid Residues ◽  
Marine Vibrio ◽  
Key Sites

Chitinase, as one of the most important extracellular enzymes in the marine environment, has great ecological and applied values. In this study, two chitinases (Chi1557 and Chi4668) with 97.33% amino acid sequences identity were individually found in Vibrio rotiferianus and Vibrio harveyi. They both were encoding by 561 amino acids, but differed in 15 amino acids and showed different enzymatic properties. The optimal temperature and pH ranges were 45–50 °C and pH 5.0–7.0 for Chi1557, while ~50 °C and pH 3.0–6.0 for Chi4668. K+, Mg2+, and EDTA increased the enzymatic activity of Chi4668 significantly, yet these factors were inhibitory to Chi1557. Moreover, Chi1557 degraded colloidal chitin to produce (GlcNAc)2 and minor GlcNAc, whereas Chi4668 produce (GlcNAc)2 with minor (GlcNAc)3 and (GlcNAc)4. The Kcat/Km of Chi4668 was ~4.7 times higher than that of Chi1557, indicating that Chi4668 had stronger catalytic activity than Chi1557. Furthermore, site-directed mutagenesis was performed on Chi1557 focusing on seven conserved amino acid residues of family GH18 chitinases. Chi1557 was almost completely inactive after Glu154, Gln219, Tyr221, or Trp312 was individually mutated, retained ~50% activity after Tyr37 was mutated, and increased two times activity after Asp152 was mutated, indicating that these six amino acids were key sites for Chi1557.

scholarly journals A truncated laminin chain homologous to the B2 chain: structure, spatial expression, and chromosomal assignment.

1992 ◽  
Vol 119 (3) ◽  
pp. 679-693 ◽  
Author(s):  
P Kallunki ◽  
K Sainio ◽  
R Eddy ◽  
M Byers ◽  
T Kallunki ◽  
...  
Keyword(s):  
Amino Acid ◽  
Chain Structure ◽  
Amino Acid Sequences ◽  
Northern Analysis ◽  
Chain Gene ◽  
Chromosomal Assignment ◽  
The Novel ◽  
Putative Signal Peptide ◽  
Human Fetal Tissues ◽  
Domain I

We describe the identification of a novel laminin chain. Overlapping clones were isolated from a human fibrosarcoma HT1080 cell cDNA library spanning a total of 5,200 bp. A second set of clones contained an alternative 3' end sequence giving a total of 4,316 bp. The longer sequence contained an open reading frame for a 1,193-residue-long polypeptide. The alternative sequence was shortened at the carboxyl-terminal end coding for a 1,111-residue-long polypeptide. The amino acid sequence contained 21 amino acids of a putative signal peptide and 1,172 residues or alternatively 1,090 residues of a sequence with five distinct domains homologous to domains I-V in laminin chains. Comparison of the amino acid sequences showed that the novel laminin chain is homologous to the laminin B2 chain. However, the structure of the novel laminin chain isolated here differs significantly from that of the B2 chain in that it has no domain VI and domains V, IV, and III are shorter, resulting in a truncated laminin chain. The alternative sequence had a shortened domain I/II. In accordance with the current nomenclature, the chain characterized here is termed B2t. Calculation of possible chain interactions of laminin chains with the B2t chain domain I/II indicated that the B2t chain can replace the B2 chain in some laminin molecules. The gene for the laminin B2t chain (LAMB2T) was localized to chromosome 1q25-q31 in close proximity to the laminin B2 chain gene. Northern analysis showed that the B2t chain is expressed in several human fetal tissues but differently from the laminin B1 and B2 chains. By in situ hybridization expression of the B2t chain was localized to specific epithelial cells in skin, lung, and kidney as opposed to a general epithelial and endothelial cell expression of the laminin B2 chain in the same tissues.

scholarly journals Enzymatic Properties of Dipeptidyl Aminopeptidase IV Produced by the Periodontal Pathogen Porphyromonas gingivalis and Its Participation in Virulence

2000 ◽  
Vol 68 (2) ◽  
pp. 716-724 ◽  
Author(s):  
Yumi Kumagai ◽  
Kiyoshi Konishi ◽  
Tomoharu Gomi ◽  
Hisao Yagishita ◽  
Ayako Yajima ◽  
...  
Keyword(s):  
Amino Acid ◽  
Porphyromonas Gingivalis ◽  
Catalytic Domain ◽  
Animal Experiments ◽  
Catalytic Triad ◽  
Amino Acid Sequences ◽  
Enzymatic Properties ◽  
Site Directed Mutagenesis ◽  
Periodontal Pathogen ◽  
Dipeptidyl Aminopeptidase

ABSTRACT Porphyromonas gingivalis is a major pathogen associated with adult periodontitis. We cloned and sequenced the gene (dpp) coding for dipeptidyl aminopeptidase IV (DPPIV) fromP. gingivalis W83, based on the amino acid sequences of peptide fragments derived from purified DPPIV. An Escherichia coli strain overproducing P. gingivalis DPPIV was constructed. The enzymatic properties of recombinant DPPIV purified from the overproducer were similar to those of DPPIV isolated fromP. gingivalis. The three amino acid residues Ser, Asp, and His, which are thought to form a catalytic triad in the C-terminal catalytic domain of eukaryotic DPPIV, are conserved in P. gingivalis DPPIV. When each of the corresponding residues of the enzyme was substituted with Ala by site-directed mutagenesis, DPPIV activity significantly decreased, suggesting that these three residues of P. gingivalis DPPIV are involved in the catalytic reaction. DPPIV-deficient mutants of P. gingivalis were constructed and subjected to animal experiments. Mice injected with the wild-type strain developed abscesses to a greater extent and died more frequently than those challenged with mutant strains. Mice injected with the mutants exhibited faster recovery from the infection, as assessed by weight gain and the rate of lesion healing. This decreased virulence of mutants compared with the parent strain suggests that DPPIV is a potential virulence factor of P. gingivalis and may play important roles in the pathogenesis of adult periodontitis induced by the organism.

scholarly journals Proteins encoded by Novel ORFs have increased disorder but can be biochemically regulated and harbour pathogenic mutations

2019 ◽  
Author(s):  
N. Suhas Jagannathan ◽  
Narendra Meena ◽  
Kethaki Prathivadi Bhayankaram ◽  
Sudhakaran Prabakaran
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequences ◽  
Open Reading Frames ◽  
The Novel ◽  
Biological Functions ◽  
Novel Proteins ◽  
Coding Regions ◽  
Disordered Structures ◽  
Reading Frames ◽  
Computational Predictions

AbstractRecent evidence has suggested that protein or protein-like products can be encoded by previously uncharacterized Open Reading Frames (ORFs) that we define as Novel Open Reading Frames (nORFs)1,2. These nORFs are present in both coding and non coding regions of the human genome and the novel proteins that they encode have increased the number and complexity of cellular proteome from bacteria to humans. It is a conundrum whether these protein or protein-like products could play any significant functional biological role. But hopes have been raised to target them for anticancer and antimicrobial therapy3,4. To infer whether these novel proteins can perform biological functions, we used computational predictions to systematically investigate whether their amino acid sequences can form ordered or disordered structures. Our results indicated that that these novel proteins have significantly higher predicted disorder structure compared to all known proteins, yet we do not find any correlation between the pathogenicity of the mutations and whether they are present in the ordered and disordered regions of these novel proteins. This study reveals that we should investigate these novel proteins more systematically as they may be important to understand complex diseases.

A novel gene, MEL1, mapped to 1p36.3 is highly homologous to the MDS1/EVI1 gene and is transcriptionally activated in t(1;3)(p36;q21)-positive leukemia cells

Blood ◽  
2000 ◽  
Vol 96 (9) ◽  
pp. 3209-3214 ◽  
Author(s):  
Naomi Mochizuki ◽  
Seiichi Shimizu ◽  
Toshiro Nagasawa ◽  
Hideo Tanaka ◽  
Masafumi Taniwaki ◽  
...  
Keyword(s):  
Amino Acid ◽  
Transcriptional Activation ◽  
Zinc Finger Protein ◽  
Fetal Liver ◽  
Amino Acid Sequences ◽  
Leukemia Cells ◽  
The Novel ◽  
Amino Acid Residues ◽  
Novel Gene ◽  
Pr Domain

Abstract The reciprocal translocation t(1;3)(p36;q21) occurs in a subset of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), which is frequently characterized by trilineage dysplasia, in particular dysmegakaryocytopoiesis, and poor prognosis. Previously, the breakpoint cluster region (BCR) at 3q21 was identified within a 60-kilobase (kb) region centromeric to the BCR of 3q21q26 syndrome and that at 1p36.3 within a 90-kb region. In this study, genes were searched near the breakpoints at 1p36.3, and a novel gene was isolated that encoded a zinc finger protein with a PR domain, which is highly homologous to theMDS1/EVI1 gene. The novel gene, designated asMEL1(MDS1/EVI1-like gene 1), with 1257 amino acid residues is 64% similar in nucleotide and 63% similar in amino acid sequences to MDS1/EVI1 with the same domain structure. The MEL1 gene is expressed in leukemia cells with t(1;3) but not in other cell lines or bone marrow, spleen, and fetal liver, suggesting that MEL1 is specifically in the t(1;3)(p36;q21)-positive MDS/AML. On the basis of the positional relationship between the EVI1 and MEL1 genes in each translocation, it was suggested that both genes are transcriptionally activated by the translocation of the 3q21 region with the Ribophorin I gene. Because of the transcriptional activation of the EVI1 family genes in both t(1;3)(p36;q21)-positive MDS/AML and 3q21q26 syndrome, it is suggested that they share a common molecular mechanism for the leukemogenic transformation of the cells.

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