Construction of Mycobacterium tuberculosis cdd knockout and evaluation of invasion and growth in macrophages.

Cytidine deaminase (MtCDA), encoded by cdd gene (Rv3315c), is the only enzyme identified in nucleotide biosynthesis pathway of Mycobacterium tuberculosis that is able to recycle cytidine and deoxycytidine. An M. tuberculosis knockout strain for cdd gene was obtained by allelic replacement.

Gene replacement and quantitative mass spectrometry approaches validate guanosine monophosphate synthetase as essential for growth.

Guanosine monophosphate synthetase (GMPS), encoded by gene, is a key enzyme for guanine nucleotide biosynthesis in . The gene from several bacterial pathogens has been shown to be involved in virulence; however, no information about the physiological effect of direct deletion in has been described so far. Here, we demonstrated that the gene is essential for H37Rv growth.

Experimental evidence that pristanic acid disrupts mitochondrial homeostasis in brain of young rats.

Patients affected by peroxisomal disorders commonly present neurologic dysfunction and brain abnormalities, whose neuropathology is poorly understood. Given that high sustained concentrations of pristanic acid (Prist) are found in the brain of these patients, it is conceivable that this complex branched-chain fatty acid is neurotoxic. Therefore, the present work investigated the in vitro effects of Prist at similar concentrations found in plasma of affected patients with some peroxisomal disorders on important parameters of energy homeostasis, including respiratory parameters determined by oxygen consumption, membrane potential (ΔΨm), NAD(P)H content, and swelling in mitochondrial preparations obtained from brain of young rats using glutamate plus malate or succinate as respiratory substrates.

Glycine intrastriatal administration induces lipid and protein oxidative damage and alters the enzymatic antioxidant defenses in rat brain.

Aims: We investigated the effects of in vivo intrastriatal administration of glycine (Gly), which is found at high concentrations in the brain of patients affected by nonketotic hyperglycinemia (NKH), on important parameters of oxidative stress.

Main Methods: Thiobarbituric acid-reactive substances values (TBA-RS, lipid peroxidation), carbonyl formation (protein oxidative damage), sulfhydryl content, reduced glutathione concentrations, nitric oxide production and the activities of the antioxidant enzymes glutathione peroxidase, glutathione reductase, catalase, superoxide dismutase and glucose-6-phosphate dehydrogenase (antioxidant defenses) were measured in striatum from 30-day-old rats after Gly injection.

Key Findings: Gly administration significantly increased TBA-RS values, implying lipid oxidative damage.

Neurochemical evidence that pristanic acid impairs energy production and inhibits synaptic Na(+), K(+)-ATPase activity in brain of young rats.

Pristanic acid (Prist) accumulates in some peroxisomal disorders characterized by neurologic dysfunction and brain abnormalities. The present work investigated the in vitro effects of Prist on important parameters of energy metabolism in brain cortex of young rats. CO(2) production from labeled acetate and the activities of the respiratory chain complexes I-IV, creatine kinase and synaptic Na(+), K(+)-ATPase were measured.

Experimental evidence that methylmalonic acid provokes oxidative damage and compromises antioxidant defenses in nerve terminal and striatum of young rats.

Methylmalonic acidemia and propionic acidemia are organic acidemias biochemically characterized by predominant tissue accumulation of methylmalonic acid (MMA) and propionic acid (PA), respectively. Affected patients present predominantly neurological symptoms, whose pathogenesis is not yet fully established. In the present study we investigated the in vitro effects of MMA and PA on important parameters of lipid and protein oxidative damage and on the production of reactive species in synaptosomes from cerebrum of developing rats.

Seasonal variation in glucose and neutral amino acid uptake in the estuarine crab Neohelice granulata.

This study investigates the mechanisms of glucose and amino acid transport in gills and jaw muscle of N. granulata collected from an estuarine natural population. The physicochemical parameters of the estuarine environment and of this crustacean's hemolymph were measured during different seasons of the year.

Hepatopancreas gluconeogenesis during anoxia and post-anoxia recovery in Chasmagnathus granulata crabs maintained on high-protein or carbohydrate-rich diets.

C. granulata is a semiterrestrial crab that lives in the mesolittoral and the supralittoral zones of estuaries and faces hypoxia and anoxia when exposed to atmospheric air. The carbohydrate or protein content of the diets administered to the crabs induced different metabolic adjustments during anoxia and post-anoxia recovery period.