Search PubMed⌕ Search

Biomedical subjects

M S Korczynski

Publications and source records attributed to M S Korczynski.

13 recordsLinked to original sources
PubMed1970

Cell envelope of an iron-oxidizing bacterium: studies of lipopolysaccharide and peptidoglycan.

Further structural detail is presented of the cell envelope of the chemolithotroph Ferrobacillus ferrooxidans (Thiobacillus ferrooxidans). Thin sections of purified lipopolysaccharide (LPS) and peptidoglycan show structures comparable to those seen in the envelope of intact cells, whereas negative stains of LPS appear as sheets, or ribbons, or both. The sugars common to LPS, namely, heptose, glucose, galactose, mannose, and 2-keto-3-deoxyoctulosonate, were identified. The cations, iron, calcium, and magnesium, were associated with LPS. The purified LPS had a density of 1.28 and an uncorrected sedimentation coefficient of 99.9S.

Cell Nucleus↗
PubMed1969

Kinetic studies of iron oxidation by whole cells of Ferrobacillus ferrooxidans.

A colorimetric assay was developed for studying the kinetics of iron oxidation with whole cells of the chemoautotroph, Ferrobacillus ferrooxidans. The assay was more advantageous than the conventional method of Warburg manometry because of its simplicity, rapidity, and the small amount of cells required. The assay measured Fe(3+) as a chloride complex which absorbs at 410 nm. Kinetic analysis showed the apparent K(m) for iron oxidation to be 5.4 x 10(-3)m in an unbuffered system and 2.2 x 10(-3)m in the presence of beta-alanine-SO(4) (2-) buffer. Glycine and beta-alanine buffers were used in the measurement of the pH optimum for iron oxidation; the optimum ranged from 2.5 to 3.8. The effect of pH was primarily on the V(max) while the K(m) remained constant. Added SO(4) (2-) was found to stimulate iron oxidation by increasing the V(max) of iron oxidation by whole cells, but it did not affect the K(m). Results of assays of iron oxidation in systems containing various mole percentages of SO(4) (2-) and Cl(-) indicated that Cl(-) did not inhibit iron oxidation but that SO(4) (2-) was required. Sulfate could be partially replaced by HPO(4) (2-) and HAsO(4) (2-) but not by BO(3) (-), MoO(4) (2-), NO(3) (-), or Cl(-); formate and MoO(4) (2-) inhibited iron oxidation.

Bacteria↗
PubMedDate not supplied

PDA/FDA interactions.

Explore the source record for details and available documents.

Interinstitutional Relations↗
PubMedDate not supplied

PDA's global role.

Explore the source record for details and available documents.

Certification↗
PubMedDate not supplied

The effect of closure processing on the microbial inactivation of biological indicators at the closure-container interface.

Two biological indicators are routinely used by the Hospital Products Division to demonstrate the sterilization of the closure-container interface. The use of a moist heat (Clostridium sporogenes) and a dry heat (Bacillus subtilis) biological indicator allows a better understanding of the parameters that impact sterilization of the closure-container system. The ability to sterilize a given closure-container interface is defined in large part by closure moisture and product time above 100 degrees C. The data will demonstrate several different means to alter these two key factors, thereby enhancing sterilization of the closure-container interface. A categorization of closure types and processing parameters allows for more efficient cycle development in the R&D facility and a higher success rate for the final subprocess validation in the manufacturing steam vessels.

Bacteria↗