Because bifunctional enzymes are distinctive and highly conserved products of relatively infrequent gene-fusion events, they are particularly useful markers to identify clusters of organisms at different hierarchical levels of a phylogenetic tree. Within the subdivision of gram-negative bacteria known as superfamily B, there are two distinctive types of tyrosine-pathway dehydrogenases: (1) a br...

Tomato (Solanum lycopersicum) fruit contains significant amounts of bioactive compounds, particularly multiple classes of specialized metabolites. Enhancing the synthesis and accumulation of these substances, specifically in fruits, are central for improving tomato fruit quality (e.g. flavour and aroma) and could aid in elucidate pathways of specialized metabolism. To promote the production of ...

The family Curimatidae is a fish group usually considered chromosomally conserved in their diploid number. However, some studies show small changes in the karyotype microstructure, and the presence of B chromosomes, indicating a chromosomal diversification within the group, even if structural changes in the karyotypes are not visible. Few studies associate this trait with an evolutionary patter...

The pathway of aromatic amino acid biosynthesis was initiated by the enzyme DAHP synthase. In this branched biosynthetic pathway phenylalanine, tyrosine and tryptophan are produced. This enzyme was repressed and inhibited by three said end product of aromatic amino acids. The importance of this enzyme is microbial fermentation of aromatic amino acid production. The present study envisaged the i...

Conversion of glucose and ammonium salts into tryptophan by mutants of Escherichia coli was examined as part of a feasibility study on the manufacture of tryptophan. This involved construction, largely by transduction, or a variety of multiple-mutation strains with defined genotypes. By comparing the properties of these strains, we were able to define in biochemical terms several changes that s...

Some Vibrio anguillarum strains produce a catechol-type siderophore named vanchrobactin, whose biosynthetic pathway has not been completely elucidated. In addition to the previously described genes vabA, vabC, vabB, vabE, vabF, vabS and vabH, in the present study we have identified the genes encoding a DAHP (3-deoxy-d-arabino-heptulosonate-7-phosphate) synthetase (vabG), a phosphopantheteinyl t...

The crucian carp Carassius carassius (Linnaeus, 1758), is native to many European freshwaters. Despite its wide distribution, the crucian carp is declining in both the number and sizes of populations across much of its range. Here we studied 30 individuals of a putative pure population from Helsinki, Finland. Despite clear external morphological features of C. carassius, an individual was of a ...

BACKGROUND Chromomycin A3 (CMA3) staining, either by the slide method or fluorescence microscopy, is widely used for indirect assessment of protamine deficiency in a semen sample. Flow cytometry is the most suitable tool to improve assessment accuracy, both in terms of statistical analysis and for prevention of observer variation. This study provides a simple procedure to account for merocyanin...

An experimental study was conducted between January 2002 and April 2003 for the detection of delayed hypersensitivity to Fonsecaea pedrosoi metabolic antigen (chromomycin) in skin tests. A total of 194 subjects were attended by spontaneous demand at the Infectious and Parasitic Diseases outpatient clinic of the Federal University of Maranhão-UFMA and at the Department of Microbiology, Federal U...

To determine the protective effects of exogenous melatonin following exposure to Bleomycin, Etoposide, and Cisplatin (BEP) chemotherapy on sperm parameters DNA integrity, testes nitro-oxidative status, as well histopathological, inflammatory, apoptotic alternations in rats testes. Adult male Wistar were randomly segregated into six groups (n=10/group). Groups 1, 3, 4 intraperitoneally injected ...