scholarly journals Crystal Structure of the “PhoU-Like” Phosphate Uptake Regulator from Aquifex aeolicus

2005 ◽  
Vol 187 (12) ◽  
pp. 4238-4244 ◽  
Author(s):  
Vaheh Oganesyan ◽  
Natalia Oganesyan ◽  
Paul D. Adams ◽  
Jaru Jancarik ◽  
Hisao A. Yokota ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Amino Acid ◽  
Sequence Similarity ◽  
Coiled Coil ◽  
Regulatory Function ◽  
Aquifex Aeolicus ◽  
Ribosome Recycling Factor ◽  
Hsp70 Family ◽  
The One ◽  
Almost All

ABSTRACT The phoU gene of Aquifex aeolicus encodes a protein called PHOU_AQUAE with sequence similarity to the PhoU protein of Escherichia coli. Despite the fact that there is a large number of family members (more than 300) attributed to almost all known bacteria and despite PHOU_AQUAE's association with the regulation of genes for phosphate metabolism, the nature of its regulatory function is not well understood. Nearly one-half of these PhoU-like proteins, including both PHOU_AQUAE and the one from E. coli, form a subfamily with an apparent dimer structure of two PhoU domains on the basis of their amino acid sequence. The crystal structure of PHOU_AQUAE (a 221-amino-acid protein) reveals two similar coiled-coil PhoU domains, each forming a three-helix bundle. The structures of PHOU_AQUAE proteins from both a soluble fraction and refolded inclusion bodies (at resolutions of 2.8 and 3.2Å, respectively) showed no significant differences. The folds of the PhoU domain and Bag domains (for a class of cofactors of the eukaryotic chaperone Hsp70 family) are similar. Accordingly, we propose that gene regulation by PhoU may occur by association of PHOU_AQUAE with the ATPase domain of the histidine kinase PhoR, promoting release of its substrate PhoB. Other proteins that share the PhoU domain fold include the coiled-coil domains of the STAT protein, the ribosome-recycling factor, and structural proteins like spectrin.

The gene encoding a major component of the lateral elements of synaptonemal complexes of the rat is related to X-linked lymphocyte-regulated genes

1994 ◽  
Vol 14 (2) ◽  
pp. 1137-1146
Author(s):  
J H Lammers ◽  
H H Offenberg ◽  
M van Aalderen ◽  
A C Vink ◽  
A J Dietrich ◽  
...  
Keyword(s):  
Amino Acid ◽  
Sequence Similarity ◽  
Sodium Dodecyl ◽  
Coiled Coil ◽  
Amino Acid Identity ◽  
Male Rat ◽  
Amino Acid Sequence Similarity ◽  
Gene Encoding ◽  
Synaptonemal Complexes ◽  
Complex Protein

The lateral elements of synaptonemal complexes (SCs) of the rat contain major components with relative electrophoretic mobilities (M(r)S) of 30,000 and 33,000. After one-dimensional separation of SC proteins on polyacrylamide-sodium dodecyl sulfate gels, these components show up as two broad bands. These bands contain closely related proteins, as judged from their peptide maps and immunological reactivity. Using affinity-purified polyclonal anti-30,000- and anti-33,000-M(r) component antibodies, we isolated a cDNA encoding at least one of the 30,000- or 33,000-M(r) SC components. The protein predicted from the nucleotide sequence of the cDNA, called SCP3 (for synaptonemal complex protein 3), has a molecular mass of 29.7 kDa and a pI value of 9.4. It has a potential nucleotide binding site and contains stretches that are predicted to be capable of forming coiled-coil structures. In the male rat, the gene encoding SCP3 is transcribed exclusively in the testis. SCP3 has significant amino acid similarity to the pM1 protein, which is one of the predicted products of an X-linked lymphocyte-regulated gene family of the mouse: there are 63% amino acid sequence similarity and 35% amino acid identity between the SCP3 and pM1 proteins. However, SCP3 differs from pM1 in several respects, and whether the proteins fulfill related functions is still an open question.

scholarly journals Evidence that GCN1 and GCN20, translational regulators of GCN4, function on elongating ribosomes in activation of eIF2alpha kinase GCN2.

1997 ◽  
Vol 17 (8) ◽  
pp. 4474-4489 ◽  
Author(s):  
M J Marton ◽  
C R Vazquez de Aldana ◽  
H Qiu ◽  
K Chakraburtty ◽  
A G Hinnebusch
Keyword(s):  
Amino Acid ◽  
Sequence Similarity ◽  
Amino Acid Transporter ◽  
Translation Initiation Factor ◽  
Initiation Factor ◽  
Regulatory Function ◽  
Physical Interaction ◽  
Coupling Mechanism ◽  
Acid Transporter ◽  
Stimulation Of

In the yeast Saccharomyces cerevisiae, phosphorylation of translation initiation factor eIF2 by protein kinase GCN2 leads to increased translation of the transcriptional activator GCN4 in amino acid-starved cells. The GCN1 and GCN20 proteins are components of a protein complex required for the stimulation of GCN2 kinase activity under starvation conditions. GCN20 is a member of the ATP-binding cassette (ABC) family, most of the members of which function as membrane-bound transporters, raising the possibility that the GCN1/GCN20 complex regulates GCN2 indirectly as an amino acid transporter. At odds with this idea, indirect immunofluorescence revealed cytoplasmic localization of GCN1 and no obvious association with plasma or vacuolar membranes. In addition, a fraction of GCN1 and GCN20 cosedimented with polysomes and 80S ribosomes, and the ribosome association of GCN20 was largely dependent on GCN1. The C-terminal 84% of GCN20 containing the ABCs was found to be dispensable for complex formation with GCN1 and for the stimulation of GCN2 kinase function. Because ABCs provide the energy-coupling mechanism for ABC transporters, these results also contradict the idea that GCN20 regulates GCN2 as an amino acid transporter. The N-terminal 15 to 25% of GCN20, which is critically required for its regulatory function, was found to interact with an internal segment of GCN1 similar in sequence to translation elongation factor 3 (EF3). Based on these findings, we propose that GCN1 performs an EF3-related function in facilitating the activation of GCN2 by uncharged tRNA on translating ribosomes. The physical interaction between GCN20 and the EF3-like domain in GCN1 could allow for modulation of GCN1 activity, and the ABC domains in GCN20 may be involved in this regulatory function. A human homolog of GCN1 has been identified, and the portion of this protein most highly conserved with yeast GCN1 has sequence similarity to EF3. Thus, similar mechanisms for the detection of uncharged tRNA on translating ribosomes may operate in yeast and human cells.

The Crystal Structure of Indospicine Hydrochloride Hydrate

1992 ◽  
Vol 45 (6) ◽  
pp. 1021 ◽  
Author(s):  
MP Hegarty ◽  
CHL Kennard ◽  
KA Byriel ◽  
G Smith
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Amino Acid ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
A Cell ◽  
Independent Molecules ◽  
The One

The crystal structure of the hepatotoxic amino acid indospicine [L-6-amidino-2-aminohexanoic acid, (S)-2,7-diamino-7-iminoheptanoic acid], as its hydrochloride hydrate, has been determined by X-ray diffraction and refined to a residual R 0.036 for 845 observed reflections collected at 173 K. Crystals are orthorhombic, space group P 22121 with 8 molecules in a cell of dimensions a 5.1541(4), b 14.083(1), c 31.781(3) � . The structure is consistent with the one previously derived from chemical data but with the presence of a terminal amidinium ion and an α-amino acid zwitterion pair. The two independent molecules in the asymmetric unit are conformationally different and form a head-to-tail packing motif linked by NH(amidino)…O(carboxyl) hydrogenbonds (N…O,2.80, 2.85 � ). The structure also features extensive hydrogen bonding involving the water of solvation.

scholarly journals The gene encoding a major component of the lateral elements of synaptonemal complexes of the rat is related to X-linked lymphocyte-regulated genes.

1994 ◽  
Vol 14 (2) ◽  
pp. 1137-1146 ◽  
Author(s):  
J H Lammers ◽  
H H Offenberg ◽  
M van Aalderen ◽  
A C Vink ◽  
A J Dietrich ◽  
...  
Keyword(s):  
Amino Acid ◽  
Sequence Similarity ◽  
Sodium Dodecyl ◽  
Coiled Coil ◽  
Amino Acid Identity ◽  
Male Rat ◽  
Amino Acid Sequence Similarity ◽  
Gene Encoding ◽  
Synaptonemal Complexes ◽  
Complex Protein

The lateral elements of synaptonemal complexes (SCs) of the rat contain major components with relative electrophoretic mobilities (M(r)S) of 30,000 and 33,000. After one-dimensional separation of SC proteins on polyacrylamide-sodium dodecyl sulfate gels, these components show up as two broad bands. These bands contain closely related proteins, as judged from their peptide maps and immunological reactivity. Using affinity-purified polyclonal anti-30,000- and anti-33,000-M(r) component antibodies, we isolated a cDNA encoding at least one of the 30,000- or 33,000-M(r) SC components. The protein predicted from the nucleotide sequence of the cDNA, called SCP3 (for synaptonemal complex protein 3), has a molecular mass of 29.7 kDa and a pI value of 9.4. It has a potential nucleotide binding site and contains stretches that are predicted to be capable of forming coiled-coil structures. In the male rat, the gene encoding SCP3 is transcribed exclusively in the testis. SCP3 has significant amino acid similarity to the pM1 protein, which is one of the predicted products of an X-linked lymphocyte-regulated gene family of the mouse: there are 63% amino acid sequence similarity and 35% amino acid identity between the SCP3 and pM1 proteins. However, SCP3 differs from pM1 in several respects, and whether the proteins fulfill related functions is still an open question.

scholarly journals The Diagnosis and Therapy of Degenerative Knee Joint Disease: Expert Consensus from the Chinese Pain Medicine Panel

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Dong Huang ◽  
Yan-Qing Liu ◽  
Li-Shuang Liang ◽  
Xue-Wu Lin ◽  
Tao Song ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Diagnosis And Treatment ◽  
Joint Disease ◽  
Knee Joints ◽  
Reproduction Rate ◽  
Pain Specialist ◽  
Chinese Association ◽  
The One ◽  
Almost All ◽  
Based Medicine

At present, there are many constantly updated guidelines and consensuses on the diagnosis and treatment of osteoarthritis both at home and abroad. The recommendations established using methods of evidence-based medicine has experienced strict research on controlling bias and promoting reproduction rate. As a result, the previous evidence was reevaluated, and a lot of changes were provoked in the diagnosis and treatment concept of osteoarthritis. However, several methods not recommended by foreign guidelines are still in use in the current clinical practice in China. On the one hand, Chinese experts have not reached extensive consensus on whether it is necessary to make changes according to foreign guidelines. On the other hand, almost all the current relevant guidelines are on osteoarthritis, but the lesions around knee joints which, as a whole, bear the largest weight in human body, cannot be ignored. For this purpose, Chinese Association for the Study of Pain (CASP) organized some leading experts to formulate this Chinese Pain Specialist Consensus on the diagnosis and treatment of degenerative knee osteoarthritis (DKOA) in combination with the guidelines in foreign countries and the expert experience of clinical practice in China. The consensus, which includes the definition, pathophysiology, epidemiology, clinical manifestation, diagnostic criteria, and treatments of DKOA, is intended to be used by first-line doctors, including pain physicians to manage patients with DKOA.

scholarly journals Itaconate Alters Succinate and Coenzyme A Metabolism via Inhibition of Mitochondrial Complex II and Methylmalonyl-CoA Mutase

Metabolites ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 117
Author(s):  
Thekla Cordes ◽  
Christian M. Metallo
Keyword(s):  
Amino Acid ◽  
Metabolic Pathways ◽  
Mammalian Cells ◽  
Coenzyme A ◽  
Cultured Cells ◽  
Tca Cycle ◽  
Regulatory Function ◽  
Reversible Inhibitor ◽  
Complex Ii ◽  
Branched Chain

Itaconate is a small molecule metabolite that is endogenously produced by cis-aconitate decarboxylase-1 (ACOD1) in mammalian cells and influences numerous cellular processes. The metabolic consequences of itaconate in cells are diverse and contribute to its regulatory function. Here, we have applied isotope tracing and mass spectrometry approaches to explore how itaconate impacts various metabolic pathways in cultured cells. Itaconate is a competitive and reversible inhibitor of Complex II/succinate dehydrogenase (SDH) that alters tricarboxylic acid (TCA) cycle metabolism leading to succinate accumulation. Upon activation with coenzyme A (CoA), itaconyl-CoA inhibits adenosylcobalamin-mediated methylmalonyl-CoA (MUT) activity and, thus, indirectly impacts branched-chain amino acid (BCAA) metabolism and fatty acid diversity. Itaconate, therefore, alters the balance of CoA species in mitochondria through its impacts on TCA, amino acid, vitamin B12, and CoA metabolism. Our results highlight the diverse metabolic pathways regulated by itaconate and provide a roadmap to link these metabolites to potential downstream biological functions.

Sign in / Sign up

Export Citation Format

Share Document