Cellular Reserve Research Articles

Storage-induced denitrification using sequencing batch reactor operation

As a biochemical reduction of oxidized-nitrogen species, the denitrification reaction requires the availability of an electron-donor substrate. This requirement is typically satisfied by the provision of an organic carbon supplement or, possibly, a reactor design which utilizes raw-waste organic carbon components. Bacterial storage can also provide the necessary electron source. However, in the instance of conventional wastewater treatment facilities, the limited availability of such cellular reserve material results in a markedly reduced denitrification capacity. Bench-scale studies of storage induced denitrification were conducted using a sequencing batch reactor. By operating the reactor in a mode conducive to the development of cellular storage, the system maintained a consistent 92+% reduction in total nitrogen without a carbon supplement. Depletion of the cellular glycogen reserve was observed during the denitrification reaction.

Emendation of the Description of Pseudomonas cepacia Burkholder (Synonyms: Pseudomonas multivorans Stainer et al., Pseudomonas kingae Jonsson; EO-1 Group)

It has been reported that the names Pseudomonas multivorans, P. kingae, and P. cepacia are synonymous and that P. cepacia has priority. We have confirmed this synonymy by subjecting a larger number of strains (15 each) of P. multivorans and P. kingae to a wider variety of morphological, nutritional, physiological, and biochemical tests than employed in other studies. A total of 127 tests performed on each strain showed that the two groups of strains were 94% similar, differing only in the following nine characters: growth at 41 C; pigmentation; growth on cetrimide agar; nitrate reduction; acid from sucrose and maltose on O-F medium; utilization of nicotinate and n-dodecane as sole carbon sources; and susceptibility to nalidixic acid. Salient properties for both groups of strains are nutritional versatility and accumulation of poly-β-hydroxybutyrate as a cellular reserve material.

Changes in the Lipids of Cells from Aging Populations of Tetrahymena pyriformis*†

SYNOPSIS. Lipids in aging cultures of Tetrakymena pyriformis were extracted at various times after inoculation, purified, and weighed or chromatographed on thin layers of silica gel. The total cellular lipid increased throughout logarithmic and early stationary phases but decreased sharply after 72 hr. The amount of one lipid class, probably the triglycerides, followed the same trends. It may be a cellular reserve.

The aerobic pseudomonads: a taxonomic study.

SUMMARY A collection of 267 strains, representing many of the principal biotypes among aerobic pseudomonads, has been subjected to detailed study, with particular emphasis on biochemical, physiological and nutritional characters. A total of 146 different organic compounds were tested for their ability to serve as sources of carbon and energy. Other characters that were studied included : production of extracellular hydrolases; nitrogen sources and growth factor requirements H-chemolithotrophy; denitrifying ability; pigment production; ability to accumulate poly-p-hydroxybutyrate as a cellular reserve material; biochemical mechanisms of aromatic ring cleavage; and nature of the aerobic electron transport system. The resultant data have revealed many hitherto unrecognized characters of taxonomic significance. As a consequence, it has become possible to recognize among the biotypes examined a limited number of species which can be readily and clearly distinguished from one another by multiple, unrelated phenotypic differences.

REACTIONS OF MONKEYS TO EXPERIMENTAL MIXED INFLUENZA AND STREPTOCOCCUS INFECTIONS

1. The vital importance of the cellular defense forces in the resistance of the monkey to combined streptococcus and influenza virus infections has been demonstrated. 2. Some of the conditions prejudicial to the maintenance of an optimum cellular reserve in the infected animal have been revealed; viz., undernutrition, physical cold, intratracheal route of infection. 3. The potential threat exerted by latent foci of streptococci, and the importance, in relation to the combined infection with virus, of cellular and humoral immunity, together or separately, have been demonstrated. The essential rôle of optimum nutrition (notably as concerns the vitamin B complex, and folic acid specifically) in the prevention of disastrous illness from these infectious agents, individually or in combination, would seem to have been proven. 4. Signs of glomerular nephritis appeared in a significant number of monkeys receiving Streptococcus hemolyticus and influenza virus in sequence, followed by reinoculation or spontaneous reappearance of the streptococci. 5. Reinoculation of Streptococcus hemolyticus, group C, resulted in a prompt "booster" increase in the opsonic index. Virus instillation was followed by just as sudden a depression in this index. 6. Reinoculation failed to evoke either the granulocytosis or the leucopenia in monkeys which are characteristic effects of the streptococcus and the virus respectively when these agents are introduced for the first time by way of the nasal mucous membrane. 7. Simultaneous intranasal inoculation of influenza virus, type A, and Streptococcus hemolyticus, group C, in nutritionally normal Macaca mulatta failed to produce obvious signs of disease. In most of the animals, however, a streptococcus-induced leucocytosis followed by a delayed virus-induced granulopenia developed. 8. Inoculation of influenza virus followed in 4 to 17 days by streptococci produced obvious signs of disease in five of eleven animals which had become leucopenic as result of the action of the virus, and fatal streptococcal septicemia in two monkeys. 9. The development of signs of infection in previously healthy monkeys exposed to virus followed by streptococci confirms both the clinical and laboratory experience of other observers, that virus infection may predispose to secondary bacterial invasion, and, that at times, under unfavorable circumstances, the infection may become overwhelming. Although the complete mechanism of resistance is as yet not wholly clear, the depressant or inhibitory effect of the virus on both its cellular and humoral elements has been established.