BIOCHEMISTRY OF THE USTILAGINALES: II. ISOLATION AND PARTIAL CHARACTERIZATION OF USTILAGIC ACID

1951 ◽  
Vol 29 (5) ◽  
pp. 409-414 ◽  
Author(s):  
R. U. Lemieux ◽  
J. A. Thorn ◽  
Carol Brice ◽  
R. H. Haskins
Keyword(s):  
Molecular Weight ◽  
Metabolic Product ◽  
Partial Characterization ◽  
Methyl Groups ◽  
Molecular Formula ◽  
Carboxyl Group ◽  
Submerged Cultures ◽  
Neutralization Equivalent ◽  
Corn Smut

The needlelike crystals which form in aerated submerged cultures of the corn smut Ustilago zeae (PRL-119) were found to be a D-glucolipid, m.p. 146-7°C, [Formula: see text] (pyridine), which contained one carboxyl group, two ester groups, at least two terminal methyl groups, and two D-glucose residues per mole. On the basis of elementary analyses, neutralization equivalent, and molecular weight estimations, the molecular formula of the material isolated was approximately C37H62−6O17. The substance was not shown to be chemically homogeneous. Conditions used in culturing the fungus in stirred fermentors to produce the crystalline metabolic product, which was termed "ustilagic acid", are described, and a procedure for the isolation of the material is given.

Detection and partial characterization of extracellular inducers of persistence in Staphylococcus epidermidis and Staphylococcus aureus

2021 ◽  
Vol 70 (6) ◽  
Author(s):  
Elyse C. Curry ◽  
Ryan G. Hart ◽  
Danni Y. Habtu ◽  
Neal R. Chamberlain
Keyword(s):  
Molecular Weight ◽  
Staphylococcus Aureus ◽  
Staphylococcus Epidermidis ◽  
Type Species ◽  
Proteinase K ◽  
Partial Characterization ◽  
Content Type ◽  
Link Type ◽  
Inducing Factors

Introduction. This study describes the identification and partial characterization of persistence-inducing factors (PIFs) from staphylococci. Hypothesis/Gap Statement. Increases in persisters during mid-log phase growth indicate that quorum-sensing factors might be produced by staphylococci. Aim. To identify and partially characterize PIFs from Staphylococcus epidermidis RP62A and Staphylococcus aureus SH1000. Methodology. Others have demonstrated a significant increase in persister numbers during mid-log phase. Inducers of this mid-log increase have yet to be identified in staphylococci. Optical density at 600 nm (OD600) was used instead of time to determine when persister numbers increased during logarithmic growth. Concentrated culture filtrates (CCFs) from S. epidermidis and S. aureus were obtained at various OD600s and following incubation at 16 h. The CCFs were used to develop a PIF assay. The PIF assay was used to partially characterize PIF from S. epidermidis and S. aureus for sizing of PIF activity, temperature and protease sensitivity and inter-species communications. Results. The optimal OD600s for S. epidermidis and S. aureus PIF assays were 2.0 and 0.5, respectively. The highest PIF activity for both species was from CCF following incubation overnight (16 h). S. epidermidis ’ PIF activity was decreased by storage at 4 oC but not at 20 oC (16 h), 37 oC (1 h) or 100 oC (15 min). S. aureus ’ PIF activity was decreased following storage at 4 oC (2 weeks) and after boiling at 100 oC for 5 min but not after incubation at 37 oC (1 h). PIF activity from both species went through a 3000 molecular weight cutoff ultrafilter. Proteinase K treatment of S. aureus PIF decreased activity but did not decrease the PIF activity of S. epidermidis . PIF from S. epidermidis did not increase persisters when used to treat S. aureus cells and nor did PIF from S. aureus increase persisters when used to treat S. epidermidis cells. Conclusions. Attempts to discover PIFs for staphylococci were unsuccessful due to the time-based means used to identify mid-log. Both staphylococcal species produce extracellular, low-molecular-weight inducers of persistence when assayed using an OD600 -based PIF assay.

scholarly journals ISOLATION AND PARTIAL CHARACTERIZATION OF MACRO- AND MICRONUCLEI FROM PARAMECIUM AURELIA

1972 ◽  
Vol 53 (1) ◽  
pp. 105-115 ◽  
Author(s):  
Donald J. Cummings
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Calcium Ions ◽  
Gel Electrophoresis ◽  
Partial Characterization ◽  
Intact Cells ◽  
Molecular Weights ◽  
High Molecular Weight Species ◽  
Nonionic Detergents

A method was developed for the isolation of macro- and micronuclei from Paramecium aurelia. This method utilized ionic and nonionic detergents to rupture the intact cells, calcium ions and spermidine were employed to protect the nuclei, and the nuclei were purified by centrifugation. Macronuclei consisted of 22% DNA, 10% RNA, and 68% protein. Micronuclei were composed of 9% DNA, 11% RNA, and 80% protein. DNA from both macro- and micronuclei had a density of 1.687 g/cc in CsCl and 1.417 g/cc in Cs2SO4. These values corresponded to G + C content of about 23%. The RNA of macronuclei was examined by gel electrophoresis, and two high molecular weight species were identified having molecular Weights of 1.3 x 106 and 2.8 x 106 daltons. Three syngens were studied, and in each case the conditions for isolation of the nuclei were the same and no differences were observed in the properties of the nuclei.

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