DNA ligase I deficiency is an extremely rare primary immunodeficiency with only 6 patients reported in the literature. Most common manifestations include radiosensitivity, macrocytic anemia, lymphopenia with an increased percentage of gamma-delta T cells, and hypogammaglobulinemia requiring replacement therapy. Two-month-old girl with delayed development, T-B-NK+ SCID, and macrocytic anemia presented features of Omenn syndrome.
View Article and Find Full Text PDFBackground: Fanconi anemia (FA) is the most common inherited bone marrow failure syndrome. However, establishing its molecular diagnosis remains challenging. Chromosomal breakage analysis is the gold standard diagnostic test for this disease.
View Article and Find Full Text PDFMutations or deletions of gene are responsible for the symptoms of KBG syndrome. The KBG syndrome is a rare genetic disorder which is inherited in an autosomal dominant manner. Affected patients usually have characteristic facial features, macrodontia of the upper central incisors, hand abnormalities, developmental delay and short stature.
View Article and Find Full Text PDFBackground: Autosomal recessive mutations in the AP-4 (adaptor protein complex 4) complex subunit ϵ - 1 (AP-4E1) gene on chromosome 15q21.2 are known to cause spastic paraplegia 51 (SPG51). The exact phenotype of SPG51 remains poorly characterized, because only a few families have been reported as carriers of the mutation.
View Article and Find Full Text PDFJ Clin Med
January 2021
Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) belongs to systemic autoinflammatory diseases (AIDs). Many of these syndromes are genetically conditioned and can be inherited. Diagnosis relies on clinical symptoms and should be confirmed by genetic testing.
View Article and Find Full Text PDFThis study reports the release of complete genome sequence of the producer of bacterial nanocellulose (BNC) - Gluconacetobacter xylinus E25, a vinegar-isolated strain. Preliminary sequence analysis revealed complexity of the genome structure and familiarized genetic basis of productive properties of E25 strain. The genome consists of one chromosome and five plasmids.
View Article and Find Full Text PDFExpression of the sulfur assimilation pathway in Aspergillus nidulans is under control of sulfur metabolite repression, which is composed of scon genes encoding subunits of ubiquitin ligase and the metR gene coding for a transcriptional activator. In this paper we report three dominant suppressors of methionine requirement isolated from a metB3 diploid strain. All three mutations lead to the substitution of phenylalanine 48 by serine or leucine in the conserved N-terminal region of the MetR protein.
View Article and Find Full Text PDFDespite the extensive research efforts over the past 25 years that have focused on HIV, there is still no cure for AIDS. However, tremendous progress in the understanding of the structure and biology of the HIV virus led to the development of safe and potent HIV-based transgene delivery vectors. These genetic vehicles are referred to as lentiviral vectors.
View Article and Find Full Text PDFBiochem Biophys Res Commun
April 2007
Processing of most PC zymogens is required for successful folding and/or passage through the secretory pathway; active site mutants are retained in the ER and degraded. We here report that the active site serine mutant of PC2 (PC2-S383A) was efficiently secreted as the intact zymogen in CHO-K1 cells, suggesting that its propeptide can productively insert into the mutated binding pocket without causing misfolding. In AtT-20 cells, PC2-S383A was cleaved at the secondary cleavage site within the propeptide; this cleavage event was pH-dependent and was inhibited by a proprotein convertase inhibitor.
View Article and Find Full Text PDFBy taking advantage of the recently published furin structure, whose catalytic domain shares high homology with other proprotein convertases, we designed mutations in the catalytic domain of PC2, altering residues Ser206, Thr271, Asp278, ArgGlu282, AlaSer323, Leu341, Asn365, and Ser380, which are both conserved and specific to this convertase, and substituting residues specific to PC1 and/or furin. In order to investigate the determinants of PC2 specificity, we have tested the mutated enzymes against a set of proenkephalin-derived substrates, as well as substrates representing Arg, Ala, Leu, Phe, and Glu positional scanning variants of a peptide B-derived substrate. We found that the exchange of the Ser206 residue with Arg or Lys led to a total loss of activity.
View Article and Find Full Text PDFBacillus anthracis synthesizes two toxins composed of the three proteins: protective antigen (PA), lethal factor (LF), and edema factor (EF). The cleavage of PA on the cell surface by the convertase furin leads to the translocation of LF and EF into the cytosol. We have investigated the cross-inhibitory activities of the furin inhibitors hexa-d-arginine amide (D6R) and nona-d-arginine amide (D9R), which block the proteolytic activation of PA; and of the LF inhibitor In-2-LF, a peptide hydroxamate.
View Article and Find Full Text PDFPolyarginine-containing peptides represent potent inhibitors of furin, a mammalian endoprotease that plays an important role in metabolism, activation of pathogenic toxins, and viral proliferation. The therapeutic use of D-polyarginines is especially interesting because they are not cleaved by furin and possess inhibitory potency almost equal to L-polyarginines. In this study we attempted to determine the important elements within polyarginines that contribute to effective inhibition.
View Article and Find Full Text PDFRoles played by homocysteine and choline in the regulation of MS (methionine synthase) have been examined in fungi. The Aspergillus nidulans metH gene encoding MS was cloned and characterized. Its transcription was not regulated by methionine, but was enhanced by homocysteine and repressed by choline and betaine.
View Article and Find Full Text PDFThe arginine catabolism gene otaA encoding ornithine transaminase (OTAse) is specifically induced by arginine and is under the control of the broad-domain carbon and nitrogen repression systems. Arginine induction is mediated by a product of arcA gene coding for Zn(2)C(6) activator. We have identified a region responsible for arginine induction in the otaA promoter (AnUAS(arg)).
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