l-Glutamate is a multifunctional amino acid involved in taste perception, intermediary metabolism, and excitatory neurotransmission. In addition, recent studies have uncovered new roles for l-glutamate in gut-brain axis activation and energy homeostasis. l-Glutamate receptors and their cellular transduction molecules have recently been identified in gut epithelial cells. Stimulation of such l-g...

Immunoblot studies of synaptic membranes isolated from rat brain using antibodies raised against a previously purified glutamate-binding protein (GBP) indicated labeling of an approximately 70-kDa protein band. Since the antibodies used were raised against a 14-kDa GBP, the present studies were undertaken to explore the possibility that the 14-kDa protein may have been a proteolytic fragment of...

The enzymic synthesis of N-acetylglutamate was studied in extracts of higher plant tissues, especially in sugar beet leaves (Beta vulgaris L.). Sugar beet leaves had an enzyme that transferred the acetyl group either from acetyl-CoA or from N(2)-acetylornithine to glutamate. The enzyme was so unstable that special precautions were necessary for its detection and appreciable purification was imp...

The rat brain L-glutamate/L-aspartate transporter GLAST-1 is a member of a family of Na(+)-dependent high-affinity L-glutamate transporters proposed to be involved in the termination and modulation of excitatory neurotransmitter signals. Application of electrophysiological and radiotracer techniques on Xenopus oocytes expressing cloned GLAST-1 revealed that the apparent Km value of the transpor...

Drug addiction has developed to a social illness. Changes in glutamate transmission have been recorded by the repeated administration of addictive drugs into VTA. In this investigation, In vivo microdialysis was used to study the effects of morphine on glutamate release from the ventral tegmentum area (VTA) in freely moving rats. Rats were anesthetized with chloral hydrate (350 mg/kg, i.p.) and...

L-lactate is one of main byproducts excreted in to the fermentation medium. To improve L-glutamate production and reduce L-lactate accumulation, L-lactate dehydrogenase-encoding gene ldhA was knocked out from L-glutamate producing strain Corynebacterium glutamicum GDK-9, designated GDK-9ΔldhA. GDK-9ΔldhA produced approximately 10.1% more L-glutamate than the GDK-9, and yielded lower levels of s...

Quisqualate, a glutamate analogue, displaced L-[3H]glutamate binding in a biphasic manner, corresponding to "high-affinity" and "low-affinity" binding sites. High-affinity quisqualate sites were termed "quisqualate-sensitive L-[3H]glutamate" binding sites. Quisqualate-sensitive L-[3H]glutamate binding was regionally distributed, with the highest levels present in the cerebellar molecular layer....

Glutamate transporters are expressed throughout the CNS where their major role is to clear released glutamate from presynaptic terminals. Here, we report a novel function of the transporter in rat pinealocytes. This electrogenic transporter conducted inward current in response to L-glutamate and L- or D-aspartate and depolarized the membrane in patch-clamp experiments. Ca2+ imaging demonstrated...

Drug addiction has developed to a social illness. Changes in glutamate transmission have been recorded by the repeated administration of addictive drugs into VTA. In this investigation, In vivo microdialysis was used to study the effects of morphine on glutamate release from the ventral tegmentum area (VTA) in freely moving rats. Rats were anesthetized with chloral hydrate (350 mg/kg, i.p.) and...

Osteoclasts are involved in the catabolism of the bone matrix and eliminate the resulting degradation products through transcytosis, but the molecular mechanism and regulation of transcytosis remain poorly understood. Upon differentiation, osteoclasts express vesicular glutamate transporter 1 (VGLUT1), which is essential for vesicular storage and subsequent exocytosis of glutamate in neurons. V...