Inactive strains of actinomycetes isolated from natural sources were treated with ethidium bromide, an intercalating agent. After the treatment the cultures formed active variants at a frequency of more than 0.1 per cent which was rather high. 41 out of 93 cultures formed variants active against gram-positive bacteria. The majority of the active variants synthesized antibiotics only on agarized media. Daunorubicin was also used as an intercalating agent and shown to induce at a high frequency the formation of active variants with the same antibacterial spectrum as the variants induced by ethidium bromide. Induction of antibiotic production by the intercalating agents in the inactive strains of actinomycetes was likely due to the activation of the silent genes responsible for the biosynthesis of secondary metabolites.
Download full-text PDF |
Source |
|---|
Publication Analysis
Top Keywords
Similar Publications
A compound heterozygous mutation causes congenital thrombotic thrombocytopenic purpura: a case report.
Front Med (Lausanne)
January 2025
Department of Hematology, The Second Affiliated Hospital of Nanchang University, Nanchang, China.
Congenital thrombotic thrombocytopenic purpura (cTTP) is a thrombotic microangiopathy (TMA) characterized by severe hereditary ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin type 1 motifs 13) deficiency caused by mutations. This rare autosomal recessive genetic disorder is often misdiagnosed as immune thrombocytopenia (ITP) or hemolytic uremic syndrome (HUS). Here, we report a 21-year-old male cTTP patient with a compound heterozygous mutation.
View Article and Find Full Text PDFProteasome inhibitors prevent tumor cell proliferation in HHV-8-unrelated PEL-like lymphoma.
Leuk Res Rep
December 2024
Tokyo Women's Medical University, Adachi Medical Center, Department of Medicine, 4-33-1 Kohoku Adachi-ku, Tokyo, Japan.
Primary effusion lymphoma (PEL)-like lymphoma is a rare variant of PEL that exhibits diverse clinical behaviors, ranging from mild to aggressive disease courses. The clinicopathological features and effective treatments for this type of lymphoma have not been well defined. We found that proteasome inhibitors were effective in inhibiting the growth and survival of OGU1 cells, which were derived from a patient with aggressive PEL-like lymphoma, highlighting the critical role of proteasome activity in the proliferation of PEL-like lymphoma cells.
View Article and Find Full Text PDFEvaluation of the Clinicopathological Features Associated With Malignancy of Phyllodes Tumor of the Breast.
Cureus
December 2024
Department of Medicine, ASEAB (Association for Socio-Economic Advancement of Bangladesh) Community Hospital and Diagnostic Center, Pabna, BGD.
Objective: Phyllodes tumor (PT) is a variant of fibroepithelial proliferations of the breast, histologically demonstrating a leaf-like pattern. The WHO has categorized PTs as benign, borderline, or malignant based on their histological characteristics. The objective of this paper is to assess the clinicopathological factors with malignancy in PT of the breast.
View Article and Find Full Text PDFPurine Nucleoside Phosphorylase Deficiency: A Case Report of an Extremely Rare Disorder.
Cureus
December 2024
Pediatric Neurology, Armed Forces Hospital Southern Region, Khamis Mushayt, SAU.
Purine nucleoside phosphorylase (PNP) deficiency is one of the very rare types of immune deficiency disorders inherited in an autosomal recessive (AR) manner. PNP deficiency is a progressive immune disorder that can range from severe combined immunodeficiency (SCID) to combined immunodeficiency and is associated with recurrent infections, neurological manifestations, and sometimes autoimmune disorders. In our case, we describe the case of a female patient, two years and six months old, with recurrent infections, severe neutropenia, failure to thrive, and a history of a deceased sister with the same condition.
View Article and Find Full Text PDFX-Linked Autism Type 9 Caused by a Hemizygote Pathogenic Variant in the Gene: Etiological Diagnosis in an Adult Male with Moderate Intellectual Disability.
Int Med Case Rep J
January 2025
Vincent van Gogh Centre of Excellence for Neuropsychiatry, Venray, The Netherlands.
Introduction: Levocarnitine is essential for brain functioning and fatty acid metabolism and stems largely from dietary sources. The Epsilon-Trimethyllysine Hydroxylase () gene encodes the enzyme N-Trimethyllysine hydroxylase (TMLH) which catalyses the first step in the biosynthesis of carnitine. Lack of TMLH enzyme activity is associated with developmental delay and autistic behaviours described as X-linked recessive autism, type 6 (OMIM#300872).
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!