Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0032285 (
pneumonia
)
54,520
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Effects of 4-7-week feeding of naturally contaminated wheat grains containing 0.284 mg T-2 toxin/kg were investigated on the health, certain serum biochemical parameters and reproductive status of sexually mature, virgin female rabbits. Three of the ten contaminated animals died before the end of the experiment (acute, fibrinous-purulent peritonitis and
pneumonia
). Hepatic damages are suggested by significant serum alanine aminotransferase and slight aspartate aminotransferase, gamma-glutamyl transferase,
malate dehydrogenase
activity increases, as well as by cholinesterase activity decrease as compared to control animals. The damage of kidney function is indicated by significantly higher creatinine level, as compared to the control. The T-2 toxin feeding also impaired ovarian functions, reflecting by unaltered progesteron concentration, macro- and microscopical pictures after GnRH-stimulation.
...
PMID:Biochemical and physiological effects of long-term sublethal T-2 toxin feeding in rabbits. 774 Sep 2
Pneumocystis carinii is an opportunistic pathogen that causes
pneumonia
in immunocompromised patients. To investigate the genetic diversity of P. carinii populations, multilocus enzyme electrophoresis was used to analyze five enzyme systems (
malate dehydrogenase
, glucose phosphate isomerase, leucine aminopeptidase, malic enzyme, and 6-phosphogluconate dehydrogenase). Only five different multilocus associations (zymodemes) were recorded for the 70 isolates studied. While only one multilocus combination was found in mice and rabbits, three different multilocus associations were recorded in rats. Population genetic tests and phylogenetic analysis strongly suggest that P. carinii genotypes are host-specific, in agreement with molecular study results, and that no genetic exchange occurs between genotypes from different host species. This hypothesis could be verified only by the evolutionary genetic approach, which relies here on multilocus analysis.
...
PMID:Isoenzyme diversity in Pneumocystis carinii from rats, mice, and rabbits. 904 38
Chaperonins are essential for cellular growth under normal and stressful conditions and consequently represent one of the most conserved and ancient protein classes. The paradigm
Escherichia coli
chaperonin, EcGroEL, and its cochaperonin, EcGroES, assist in the folding of proteins via an ATP-dependent mechanism. In addition to the presence of
groEL
and
groES
homologs,
groEL
paralogs are found in many bacteria, including pathogens, and have evolved poorly understood species-specific functions.
Chlamydia
spp., which are obligate intracellular bacteria, have reduced genomes that nonetheless contain three
groEL
genes,
Chlamydia groEL
(
ChgroEL
),
ChgroEL2
, and
ChgroEL3
We hypothesized that ChGroEL is the bona fide chaperonin and that the paralogs perform novel
Chlamydia
-specific functions. To test our hypothesis, we investigated the biochemical properties of ChGroEL and its cochaperonin, ChGroES, and queried the
in vivo
essentiality of the three
ChgroEL
genes through targeted mutagenesis in
Chlamydia trachomatis
ChGroEL hydrolyzed ATP at a rate 25% of that of EcGroEL and bound with high affinity to ChGroES, and the ChGroEL-ChGroES complex could refold
malate dehydrogenase
(
MDH
). The chlamydial ChGroEL was selective for its cognate cochaperonin, ChGroES, while EcGroEL could function with both EcGroES and ChGroES. A P35T ChGroES mutant (ChGroESP35T) reduced ChGroEL-ChGroES interactions and
MDH
folding activities but was tolerated by EcGroEL. Both ChGroEL-ChGroES and EcGroEL-ChGroESP35T could complement an EcGroEL-EcGroES mutant. Finally, we successfully inactivated both paralogs but not
ChgroEL
, leading to minor growth defects in cell culture that were not exacerbated by heat stress. Collectively, our results support novel functions for the paralogs and solidify ChGroEL as a bona fide chaperonin that is biochemically distinct from EcGroEL.
IMPORTANCE
Chlamydia
is an important cause of human diseases, including
pneumonia
, sexually transmitted infections, and trachoma. The chlamydial chaperonin ChGroEL and chaperonin paralog ChGroEL2 have been associated with survival under stress conditions, and ChGroEL is linked with immunopathology elicited by chlamydial infections. However, their exact roles in bacterial survival and disease remain unclear. Our results further substantiate the hypotheses that ChGroEL is the primary chlamydial chaperonin and that the paralogs play specialized roles during infection. Furthermore, ChGroEL and the mitochondrial GroEL only functioned with their cochaperonin, in contrast to the promiscuous nature of GroEL from
E. coli
and
Helicobacter pylori
, which might indicate a divergent evolution of GroEL during the transition from a free-living organism to an obligate intracellular lifestyle.
...
PMID:Biochemical and Genetic Analysis of the Chlamydia GroEL Chaperonins. 2839 49