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:C0271188 (
Halo
)
461
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Several versions of methods for the indirect detection of expression of staphylococcal protein A gene (spa) in Escherichia coli (E. coli) were devised by making use of biological properties of staphylococcal protein A (SpA). i) Hemagglutination of sheep red blood cells (SRBC) sensitized with anti-SRBC-antibodies using heat-treated spa-transformed E. coli organisms; Native spa-transformed E. coli organisms did not agglutinate the sensitized SRBC. The heat-treatment (60 C, 4 hr) of the transformants, however, caused positive hemagglutination like SpA-positive Staphylococcus aureus (S. aureus) organisms. ii)
Halo
formation around colonies on agar plates containing normal dog serum, which is originally used for the detection of SpA of S. aureus. A mutant strain NMJ was isolated, which showed formation of the halo of precipitate due to interaction between immunoglobulin and SpA. iii) A new version of immunodetection; After lysis of the transformants grown on a nitrocellulose membrane by alkali, SpA could be directly detected by immuno-detection procedures after inactivation of endogenous
peroxidase
in bacteria by phenylhydrazine and hydrogen peroxide.
...
PMID:Some improved versions of methods for the indirect detection of staphylococcal protein A gene expressed in Escherichia coli. 158 71
Activity of catalase (EC 1.11.1.6) and variable fluorescence (F) were measured in sections of rye leaves (Secale cereale L. cv.
Halo
) that were exposed for 24 h to moderately high irradiance under osmotic or chemical stress conditions (paraquat, DCMU, mannitol, NaCl, CdCl
2
, CuSO
4
, Pb(NO
3
)
2
, KNO
2
, or K
2
SO
3
). Changes of the chlorophyll content and of enzyme activities related to peroxide metabolism, such as glycolate oxidase, glutathione reductase, and
peroxidase
, were assayed for comparison. In the presence of the herbicides paraquat and low DCMU concentrations that exert only partial inhibition of photosynthesis, as well as after most treatments with osmotic or chemical stress factors, catalase markedly declined due to a preferential photoinactivation. At higher DCMU levels catalase did not decline. At low KNO
2
concentrations catalase activity was preferentially increased. In general, photoinactivation of catalase was accompanied by a decline of the F/F
m
ratio, indicating photoinhibition of photosystem II, while other parameters were much more stable. Inasmuch as both catalase and the D1 reaction center protein of photosystem II have a rapid turnover in light, their steady state levels appear to decline whenever stress effects either excessively enhance deleterious oxidative conditions and degradation (e. g. Paraquat, low DCMU), or inhibit repair synthesis. Photoinactivation of catalase and of photosystem II represent specific and widely occurring early symptoms of incipient photodamage indicating stress conditions where the repair capacity is not sufficient. During prolonged exposures, e. g. to NaCl and CuSO
4
, chlorophyll was bleached in light and the rate of its photodegradation increased in proportion as the catalase level had declined. The results suggest that the enhanced susceptibility of leaf tissues to photooxidative damage which is widely observed in stressed plants is related to the early loss of catalase.
...
PMID:Preferential photoinactivation of catalase and photoinhibition of photosystem II are common early symptoms under various osmotic and chemical stress conditions. 2874 81
