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N F Millis

Publications and source records attributed to N F Millis.

9 recordsLinked to original sources

alpha-Pinene metabolism by Pseudomonas putida.

By using metabolically altered mutants and acrylate, novel putative intermediates of alpha-pinene metabolism by Pseudomonas putida PIN11 were detected. They were characterized as 3-isopropylbut-3-enoic acid and (zeta)-2-methyl-5-isopropylhexa-2,5-dienoic acid.

Acrylates

Succession of Streptococcus bovis strains with differing bacteriophage sensitivities in the rumens of two fistulated sheep.

The bacteriophage sensitivity of the Streptococcus bovis population resident in the rumens of two fistulated sheep was monitored for 112 days. During this time, three changes in the bacteriophage sensitivity of S. bovis occurred in the absence of detectable bacteriophages. Identical changes in bacteriophage sensitivity occurred simultaneously in both animals and, except for the relatively short periods of changeover in phage sensitivity, the S. bovis population in the rumens of the two sheep was homogeneous with respect to phage sensitivity.

Animals

Growth kinetics of a yeast grown on glucose or hexadecane.

The kinetics of growth of a Torulopsis sp. was investigated in a continuous culture with glucose or hexadecane as the carbon source; growth was limited by either carbon or nitrogen. The relationship between the concentration of the limited substrate and the steady-state growth rate of the organism was examined and tested against various models of growth. No existing model was found to describe the growth accurately and a new model has been proposed: (see article). It is postulated that this behavior would result from a simple first order reaction between the reactants of the rate-limiting enzymic reaction of the organism's metabolism.

Alkanes

Characterization of Streptococcus bovis bacteriophages.

About 25 Streptococcus bovis bacteriophages were isolated from abattoir wastes, bovine rumen fluid, and lysogenic strains of S. bovis. Eight phages were selected and characterized by morphology, stability, rate of adsorption, single-step growth curve, serum neutralization, and antigenic relationship. Two distinct morphological phage types were found, one of which has not been previously reported for group D streptococci.

Abattoirs

Lysogeny in Streptococcus bovis.

Forty-eight strains of Streptococcus bovis were tested for induction with mitomycin C. Eleven inducible strains were found and the lysates of all 11 contained bacteriophage-like particles. The lysate of one strain also contained large numbers of particles which closely resembled polyheads. Eight of the lysates produced zones of inhibition on indicator strains and viable bacteriophages were detected in six lysates. The sources of the S. bovis were ovine and bovine rumen fluid (23 strains), ovine and bovine feces (5 strains), blood cultures from human endocarditis (8 strains), and a wide variety of other sources (12 strains). Only 1 of 23 rumen S. bovis strains was lysogenic, which suggests that lysogenic S. bovis strains are not an important source of bacteriophages in the rumen.

Animals

Bacteriocins of Streptococcus bovis.

Forty-seven strains of Streptococcus bovis were tested for bacteriocin production. Fourteen were found to produce bacteriocins, while all 47 were sensitive to at least one of these bacteriocins. The bacteriocins, on the basis of their host range on S. bovis strains, formed six groups. A representative of each group was selected and characterized by temperature stability, sensitivity to trypsin and lipase, sedimentation by centrifugation, ability to pass through dialysis tubing, host range on other bacterial species, and conditions for production in liquid media. A correlation between mannitol fermentation and bacteriocin production was noted.

Bacteriocins