Helicobacter pylori is cause of chronic gastritis, duodenal ulcer and gastric carcinoma in humans. L-proline is a preferred energy source of the microaerophilic bacterium. Previous analyses revealed that HpputP and HpputA, the genes that are predicted to play a central role in proline metabolism as they encode for the proline transporter and proline dehydrogenase, respectively, are essential fo...

Microbial physiology plays a crucial role in whole-cell biotransformation, especially for redox reactions that depend on carbon and energy metabolism. In this study, regio- and enantio-selective proline hydroxylation with recombinant Escherichia coli expressing proline-4-hydroxylase (P4H) was investigated with respect to its interconnectivity to microbial physiology and metabolism. P4H producti...

Isolated corn mitochondria (Zea mays cv. B73 x Mo17) were fractionated and the fragments were separated on a 20-45% (weight/weight) continuous sucrose gradient. Soluble enzymes remained at the top of the gradient overlapping with the outer membranes, while inner membrane vesicles and intact inner membranes were distributed farther down the gradient. Proline oxidase and Delta(1)-pyrroline-5-carb...

While intracellular proline accumulation in response to various stress conditions has been investigated in great detail, the biochemistry and physiological relevance of proline degradation in plants is much less understood. Moreover, the second and last step in proline catabolism, the oxidation of δ(1)-pyrroline-5-carboxylic acid (P5C) to glutamate, is shared with arginine catabolism. Little in...

Flavoproteins catalyze a variety of reactions utilizing flavin mononucleotide or flavin adenine dinucleotide as cofactors. The oxidoreductase properties of flavoenzymes implicate them in redox homeostasis, oxidative stress, and various cellular processes, including programmed cell death. Here we explore three critical flavoproteins involved in apoptosis and redox signaling, ie, apoptosis-induci...

The changes in photosynthetic activity, as well the activity of nitrogen-metabolism enzymes, intensity lipid peroxidation, and proline content were studied Triticum aestivum L. plants after their incubation at a low CO2 concentration sealed chamber for 10 d. deficiency (-CO2) compared to normal (control) led decrease rate O2 gas exchange plateau light cur...

Polyethylene glycol (PEG) is often used in protein crystallography as a low-ionic-strength precipitant for crystallization and as a cryoprotectant for low-temperature data collection. Prompted by the discovery of an apparent L-lactate molecule bound in the active site of the Escherichia coli PutA proline dehydrogenase domain crystal structure, the L-lactate concentration of several PEG solution...

Aldehyde dehydrogenases (ALDHs) catalyze the NAD(P)+-dependent oxidation of aldehydes to carboxylic acids and are important for metabolism and detoxification. Although the ALDH superfamily fold is well established, some ALDHs contain an uncharacterized domain of unknown function (DUF) near the C terminus of the polypeptide chain. Herein, we report the first structure of a protein containing the...

Plant adaptation to abiotic stresses such as drought and salinity involves complex regulatory processes. Deciphering the signaling components that are involved in stress signal transduction and cellular responses is of importance to understand how plants cope with salt stress. Accumulation of osmolytes such as proline is considered to participate in the osmotic adjustment of plant cells to sali...