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The effects of selective microbial activity on hydrocarbon accelerants have been examined both in vitro and in simulated arson residues. Two groups of Pseudomonas species that assimilate components of common petroleum based accelerants have been found; one species metabolizes only aromatic hydrocarbons, the other only aliphatics. The kinetics of hydrocarbon metabolism are discussed and gas chromatographic profiles of two common accelerants that have been subjected to microbial attack are presented. Some implications and recommendations for arson investigation are discussed.

Dissertation presented in partial fulfilment of the Requirements for the Degree of Master in Biotechnology Polyhydroxyalkanoates (PHAs) constitute a group of biobased and biodegradable polymers, which have been recognized as good substitutes for petroleum-based polymers in many applications. The large-scale production of PHAs is limited by the high cost of the most commonly used carbon sources (e.g. glucose, sucrose). However, the food industry generates large amounts of wastes, including fat-containing materials that can be used as low cost carbon sources for microbial cultivation, due their high carbon content. In this study, several bacterial strains (Cupriavidus necator, Comamonas testosteroni, Pseudomonas oleovorans, P. resinovorans, P. stutzeri, and P. citronellolis) were evaluated for their ability to grow and produce PHAs using fat-containing wastes generated by the food industry. The materials used in this study were mainly composed of free fatty acids, namely mystiric, oleic, linoleic and stearic acid. In the preliminary shake flask experiments, C. necator, C. testosteroni, P. oleovorans and P. citronellolis were able to grow and produce PHA polymer on margarine waste with the highest content. Those strains were selected for batch bioreactor experiments, wherein C. necator reached the highest polymer content (56%, wt/wt) and volumetric productivity (0.33 gPHA/L.h), Lower PHA contents were achieved by P. citronellolis and P. oleovorans (7.0 and 8.5%, wt/wt, respectively). However, in contrast with C. necator that synthesized polyhydroxybutyrate [P3(HB)], those strains produced medium chain length polyesters (mcl-PHA) containing monomers of 3-hydroxyoctanoate (HO) and 3-hydroxydecanoate (HD). C. necator was also cultivated in two different fed-batch strategies. The first cultivation achieved 76% (wt/wt) of P(3HB), while high cell densities were obtained in the second cultivation (48 g/L of active biomass concentration). Finally, the P(3HB) and mcl-PHA polymers had a glass transition temperature of 0.5–7.9ºC and -45.6, a melting point of 169.3–173.4ºC and 60.9ºC, and degree of crystallinity of 48.7–56.6% and 0.7%, respectively.

Only the fluorescent pseudomonads, Pseudomonas aeruginosa, P. putida , and P. fluorescens , were sensitive to pyocins produced from P. aeruginosa .

The intraocular penetration of tobramycin sulfate, a new aminoglycoside antibiotic, was evaluated in rabbits following subconjunctival injection. The mean tobramycin sulfate concentration in the aqueous humor 60 minutes after a single 5-mg dose was 5.5 mug/ml, as compared to a mean concentration of 6.7 mug/ml following a single 10-mg dose. These levels exceed the minimal inhibitory concentration (MIC) for most Pseudomonas species and a variety of other Gram-negative bacilli recovered from clinical infection. No anterior segment changes that may be attributed to the antibiotic could be demonstrated in the injected eye.

From the culture medium of pseudomonas species pyridine derivatives were isolated which contain the (methoxythio)carbonyl (-CO-S-OCH 3 ) group thus far not described in literature

Urine screening for bacteriuria by light-scatter photometry (Autobac) was evaluated for accuracy and compared with a colony count by the calibrated loop method. Incubation time, inoculum size, precision, and interference of particulate matter were evaluated in an effort to standardize the screening procedure. Results showed that urines could be accurately screened for Enterobacteriaceae by inoculating a single Autobac cuvette chamber with 0.1 or 0.2 ml of urine and determining the voltage change after four hours. A change of greater than or equal to 0.2 units indicates significant bacteriuria. Decreased accuracy was noted for urines having greater than 10(5) cfu/ml of Pseudomonas species or gram-positive cocci, possibly because these organisms grow more slowly.

A medium is described which can be used to detect starch hydrolysis, gelatinase production, and denitrification by pseudomonads.

A Pseudomonas species, isolated from a feeder culture for Euglena viridis, shows an unusual form of tetragonal array on the external surface of the cell wall in negatively stained preparations. These regular surface [RS] layers have been demonstrated on a variety of gram positive and gram negative bacteria and form the primary interface between the cell wall and its environment. It is thought to function as a protective barrier layer against predators and other deleterious agents such as enzymes.Ammonium molybdate was the most effective negative stain at relatively high concentrations (4-8% w/v); uranyl acetate did not display the RS layer. The micrographs were investigated with the aid of optical diffraction and digital image enhancement. Areas of micrographs that were free from obvious irregularities such as stacking faults and uneven staining were selected visually, Fig. 1(a).

THE pathway by which D-galacturonic and D-glucuronic acids are utilized by phytopathogenic Pseudomonas species is apparently quite different from the uronic isomerase–keturonic reductase system found in three genera of the Enterobacteriaceae1–5. In this new pathway of uronic acid catabolism, mucic acid has been isolated and identified as the initial product following the enzymatic oxidation of D-galacturonic acid; glucaric acid is presumably formed from D-glucuronic acid.

Activities of γ-butyrobetaine hydroxylase and carnitine dehydrogenase were low in cells of Pseudomonas sp. AK 1 grown in the absence of their respective substrates.

This is a subspecialty text designed for the "medical microbiologist," presumably one who is involved in the supervision and function of a clinical microbiology laboratory. It is a diverse work with 25 chapters by 33 authors. I find four major subject divisions, although the book itself is not subdivided. Chapters 1 through 5 provide a general discussion of the handling of specimens, the adequacy of their collection, and the relevance of speciation of bacteria in medical practice. Six chapters deal with specific patient care problems. The sections on the immunosuppressed patient, microbiology of wounds, emergency microbiology, and pediatric microbiology are short and rather encyclopedic in approach. The chapter on bacteriology of sputum and John A. Washington's discussion of blood cultures are current, controversial, well written, and amply illustrated. They stand out as two of the finest chapters and can be considered stateof-the-art discussions. Pseudomonas species, mycobacteria, Chlamydia , and parasitic diseases

• The relationship between bacteremia and mortality was studied in 5882 burn patients consecutively admitted to one burn center between 1959 and 1983. Among 5877 patients with adequate data, 1481 had one or more positive blood cultures; 1529 patients died. A predictor of mortality was developed, based on data from the 4396 patients without positive blood cultures, and used to assign a discrete probability of death in the absence of bacteremia to all the patients. Comparisons were then made between observed and predicted mortality in subsets of patients with bacteremia due to (1) enteric organisms, (2) Pseudomonas species, (3) gram-positive organisms, or (4) yeastlike organisms, or without bacteremia. These comparisons indicate significantly increased mortality in patients with gram-negative bacteremia, an equivocal increase in patients with blood cultures positive for yeastlike organisms, and no increase attributable to gram-positive bacteremia. ( Arch Surg 1986;121:1027-1031)

With use of an objective numerical rating system for the assessment of the presence or absence of pneumonia on a chest x-ray film, 81 patients in the surgical intensive care unit with positive sputum cultures were assigned to either colonization (C; 39 patients) or pneumonia (P; 42 patients) groups. Respiratory failures preceding the first positive sputum culture and hepatic and/or renal failure were more frequent in the P group. Escherichia coli and Pseudomonas species, as well as polymicrobial sputa, were more common in the P group. Positive blood or pleural cultures with the same organism found in the sputum were noted in 10 of 11 P patients and only 3 of 10 C patients. Broad-spectrum antibiotic therapy directed at all sputum pathogens decreased mortality in the P group but not in the C group. We conclude that an objective rating system for chest x-ray diagnosis provides a reasonable method for separating patients with pneumonia from those with colonization. We recommend antibiotic therapy directed at all sputum pathogens in patients in surgical intensive care units. For such therapy to be successful, however, diagnostic criteria must be precise and exclude patients with colonized pathogens.

THE property of forming levan from sucrose is rather common among Bacillus species1 and is also found in Streptococcus salivarius 2 and Aerobacter levanicum 3,4 Further, levan is produced by many phytopathogenic Pseudomonas and Xanthomonas species5,6, and is said to be formed by Pseudomonas betae-gelatae 7, isolated from thawing sugar-beets. However, no mention has been made of levan-producing Pseudomonas species isolated from other than diseased or killed plant material.

Tracer experiments have shown that phenazine-1-carboxylic acid and its 5-methyl betaine are incorporated into pyocyanin by Ps. aeruginosa by decarboxylative hydroxylation. Phenazine-1,6-dicarboxylic acid is not incorporated. 2-Hydroxyphenazine-1-carboxylic acid and 2-hydroxyphenazine are derived from phenazine-1-carboxylic acid in Ps. aureofaciens but not from 5-methylphenazinium-1-carboxylate.

An outbreak of a septicaemic condition of bees occurred in East Gippsland, Victoria, during the autumn, winter, and spring of 1958. The condition appears to conform generally with cases of septicaemia recorded in Canada, United States, and France. A causative organism has been isolated from septicaemic bees in Victoria which appears to fall into the type of the Pseudomonas species of Landerkin and Katznelson (1959). This organism has been proved pathogenic to bees when inoculated by dipping or injection.

The structure of aeruginosin B is now defined as 2-amino-6-carboxy-10-methylphenazinium-8-sulphonate by the synthesis of the demethyl derivative. Aeruginosin B could not be synthesised by quaternisation of the demethyl compound or its derivatives, but has been made by the action of sulphite ion on aeruginosin A. Some limitations on the cyclisation of 2-aminodiphenylamines to phenazines in boiling nitrobenzene are described as well as a new phenazine synthesis.

5-Methylphenazinium-1-carboxylate has been synthesised. It has been converted by aqueous ammonia and cultures of Ps. aeruginosainto aeruginosin A.

ABS>The radioresistance of an unidentified species of Pseudomonas contaminating the Omega West Reactor, Los Alamos Scientific Laboratory, was determined under controlled conditions. The organism was found to be much more sensitive to gamma -radiation than originally reported. It had a D value of only 4.4 to 5.6 krad, while a population of 108 cells/ ml could be inactivated by 45 to 57.5 krad.