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Three novel Gram-positive, aerobic, actinobacterial strains, CF5/2(T), CF5/1 and CF7/1, were isolated in 2007 during environmental screening of arid desert soil in the Sahara desert, Chad. Results from riboprinting, MALDI-TOF protein spectra and 16S rRNA sequence analysis confirmed that all three strains belonged to the same species. Phylogenetic analysis of 16S rRNA sequences with the strains' closest relatives indicated that they represented a distinct species. The three novel strains also shared a number of physiological and biochemical characteristics distinct from previously named Geodermatophilus species. The novel strains' peptidoglycan contained meso-diaminopimelic acid; their main phospholipids were phosphatidylcholine, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol and a small amount of phosphatidylglycerol; MK-9(H4) was the dominant menaquinone. The major cellular fatty acids were the branched-chain saturated acids iso-C16:0 and iso-C15:0. Galactose was detected as diagnostic sugar. Based on these chemotaxonomic results, 16S rRNA gene sequence analysis and DNA-DNA hybridization between strain CF5/2(T) and the type strains of Geodermatophilus saharensis, Geodermatophilus arenarius, Geodermatophilus nigrescens, Geodermatophilus telluris and Geodermatophilus siccatus, the isolates CF5/2(T), CF5/1 and CF7/1 are proposed to represent a novel species, Geodermatophilus tzadiensis, with type strain CF5/2(T)=DSM 45416=MTCC 11411 and two reference strains, CF5/1 (DSM 45415) and CF7/1 (DSM 45420)., (Copyright © 2013 Elsevier GmbH. All rights reserved.)

Ancient mariners knew that dust whipped up from deserts by strong winds travelled long distances, including over oceans. Satellite remote sensing revealed major dust sources across the Sahara. Indeed, the Bodélé Depression in the Republic of Chad has been called the dustiest place on earth. We analysed desert sand from various locations in Chad and dust that had blown to the Cape Verde Islands. High throughput sequencing techniques combined with classical microbiological methods showed that the samples contained a large variety of microbes well adapted to the harsh desert conditions. The most abundant bacterial groupings in four different phyla included: (a) Firmicutes-Bacillaceae, (b) Actinobacteria-Geodermatophilaceae, Nocardiodaceae and Solirubrobacteraceae, (c) Proteobacteria-Oxalobacteraceae, Rhizobiales and Sphingomonadaceae, and (d) Bacteroidetes-Cytophagaceae. Ascomycota was the overwhelmingly dominant fungal group followed by Basidiomycota and traces of Chytridiomycota, Microsporidia and Glomeromycota. Two freshwater algae (Trebouxiophyceae) were isolated. Most predominant taxa are widely distributed land inhabitants that are common in soil and on the surfaces of plants. Examples include Bradyrhizobium spp. that nodulate and fix nitrogen in Acacia species, the predominant trees of the Sahara as well as Herbaspirillum (Oxalobacteraceae), a group of chemoorganotrophic free-living soil inhabitants that fix nitrogen in association with Gramineae roots. Few pathogenic strains were found, suggesting that African dust is not a large threat to public health.

Purpose: The direct influence of environmental cleanliness and risk manipulations on prepared syringes was evaluated., Methods: Media-fill testing was used to estimate potential microbial contamination. Syringes were prepared in three different environments using four different uncontrolled high-risk manipulations. The three environments included an International Organization for Standardization (ISO) class 5 horizontal laminar-airflow hood in an ISO class 6 cleanroom (in accordance with United States Pharmacopeia [USP] chapter 797), an ISO class 7 drug preparation area of an operating room, and an uncontrolled decentralized pharmacy in a ward. For each combination of environment and manipulation, 100 syringes were filled by a single operator. The four high-risk manipulations used included simple filling of syringes with trypticase soy broth, three-second contact by the ungloved fingers of the operator with the hub of the syringe, three-second contact between an object and the hub of the syringe, and exposure of the filled syringes to ambient air for 10 minutes., Results: Of the 1500 syringes prepared in three different environments, none produced within the cleanroom contained microorganisms, 6% were contaminated in the operating room, and 16% were contaminated in the ward (p < 0.0001). Certain high-risk manipulations were associated with a significant increase in the contamination of the surrogate syringes, including exposure to nonsterile ambient air and nonsterile objects or fingers (p < 0.0001)., Conclusion: High contamination rates were measured when the hub of syringes touched nonsterile environmental surfaces and fingers, whereas the drawn-air manipulation was associated with a lower risk of contamination. Working within a properly operating unidirectional airflow primary engineering control in an ISO class 5 cleanroom in accordance with USP chapter 797 requirements was demonstrated to be the best way to avoid bacterial or fungal contamination of injectable drugs directly resulting in patient infections.

Charles Darwin, like others before him, collected aeolian dust over the Atlantic Ocean and sent it to Christian Gottfried Ehrenberg in Berlin. Ehrenberg's collection is now housed in the Museum of Natural History and contains specimens that were gathered at the onset of the Industrial Revolution. Geochemical analyses of this resource indicated that dust collected over the Atlantic in 1838 originated from the Western Sahara, while molecular-microbiological methods demonstrated the presence of many viable microbes. Older samples sent to Ehrenberg from Barbados almost two centuries ago also contained numbers of cultivable bacteria and fungi. Many diverse ascomycetes, and eubacteria were found. Scanning electron microscopy and cultivation suggested that Bacillus megaterium, a common soil bacterium, was attached to historic sand grains, and it was inoculated onto dry sand along with a non-spore-forming control, the Gram-negative soil bacterium Rhizobium sp. NGR234. On sand B. megaterium quickly developed spores, which survived for extended periods and even though the numbers of NGR234 steadily declined, they were still considerable after months of incubation. Thus, microbes that adhere to Saharan dust can live for centuries and easily survive transport across the Atlantic.

Hydrogen peroxide features in many biological oxidative processes and must be continuously degraded enzymatically either via a catalatic or a peroxidatic mechanism. For this purpose ancestral bacteria evolved a battery of different heme and non-heme enzymes, among which heme-containing catalase-peroxidases (CP) are one of the most widespread representatives. They are unique since they can follow both H(2)O(2)-degrading mechanisms, the catalase activity being clearly dominant. With the fast increasing amount of genomic data available, we were able to perform an extensive search for CP and found almost 300 sequences covering a large range of microorganisms. Most of them were encoded by bacterial genomes, but we could also find some in eukaryotic organisms other than fungi, which has never been shown until now. Our screen also reveals that approximately 60% of the bacteria do not possess CP genes. Chaotic distribution among species and incongruous phylogenetic reconstruction indicated existence of numerous lateral gene transfers in addition to duplication events and regular speciation. The results obtained show an impressively complex gene transmission pattern, and give some new insights about the role of CP and the origin of life on earth. Finally, we propose for the first time bacterial candidates that may have participated in the transfer of CP from bacteria to eukaryotes.

A photosensitizer, meso-tetra(4-hydroxyphenyl)porphyrin, was incorporated into sub-150 nm nanoparticles using the emulsification-diffusion technique in order to perform sterilization by filtration using 0.22 microm membranes. The three selected polyesters (poly(D,L-lactide-co-glycolide), (50:50 PLGA, 75:25 PLGA) and poly(D,L-lactide (PLA)) for the nanoparticle production were all amorphous in nature and have similar molecular weights but different copolymer molar ratios. The influence of the copolymer molar ratio and the theoretical drug loading was investigated in terms of particle size, drug loading, entrapment efficiency and surface characteristics. With all the polymers used, sub-150 nm nanoparticles were produced with good reproducibility and narrow size distributions irrespective of both the polymer nature and the theoretical drug loading. After purification by cross-flow filtration, the nanoparticle suspensions were sterilized by membrane filtration and freeze-dried in the presence of a lyoprotectant (trehalose). For all types of nanoparticles, complete redispersion in various media could be obtained. All final freeze-dried products were refiltrable on a 0.22 microm membrane and were stable in terms of mean particle size and drug loading over a period up to 6 months. The effective drug loading increased at higher theoretical drug loading, the entrapment efficiency was however decreased. The same trend was observed with the three polyesters. The sterility of the final freeze-dried nanoparticles was confirmed by the results of the sterility testing which showed no bacterial contamination.

Twenty drugs of plant origin were analysed in order to determine the microbial contamination level. A light homogenizing method was used to avoid an increase in the antimicrobial capacity of certain drugs, which would falsify the analytical results. The total viable aerobic count (TVC) varied from 10(1) to 10(7) CFU/g and in 11 samples out of 21 was equal to or higher than 10(5) CFU/g. The number of fungi varied from one drug to another, but was generally lower than the aerobic TVC to the power of 10. No cases containing Aspergillus flavus were found. The total viable anaerobic count consisted mainly of facultative anaerobic germs. Aerobic spores and facultative anaerobic bacteria were abundant. They often represented more than 50% of the aerobic TVC and among them, Bacillus cereus was found. Concerning specified micro-organisms, Escherichia coli was found 3 times, Staphylococcus aureus 2 times and Pseudomonas (not aeruginosa) a few times. Salmonella was never found. The Enterobacteriaceae, on the other hand, were often found and in some cases their number can be greater than 10(4) CFU/g. The typed bacteria corresponded to Enterobacter spp. Some drug samples in bags were analysed. The level of contamination was identical to that found in the bulk drugs. The analysis in parallel of a black tea sample showed an aerobic TVC of 4.10(3) CFU/g. Specified micro-organisms were not found in the infusions. In comparison with non-boiled drugs, the survivors can represent up to 30% of the aerobic TVC.

Summary The authors studied the combination of Kathon(R) CG and Germall(R) II (0.1%-0.1%) in hydrophilic creams. Their objective was to find an alternative to the use of parabens. Kathon(R) CG was chosen due to its antimicrobial effectiveness and its broad spectrum of activity. It must be indicated, however, that it has only a weak action against Staphylococcus aureus. In order to reinforce its microbicidal action it was combined with Germall(R) II. The Kathon(R) CG-Germall(R) II combination showed addition, indeed even synergy, with respect to Escherichia coli (Gram negative rod) and Aspergillus niger (fungus). In the case of Candida albicans (yeast) the antifungal effect of Kathon(R) CG dominates. Finally, the combination can have effects from addition to antagonism in the case of the three strains of Staphylococcus aureus tested (Gram positive coccus). The time required to eliminate 10(6) UFC of these bacteria per g of cream can often exceed 48 h. If the concentration of Germall(R) II is increased to 0.3% then the effectiveness of the mixture is markedly reinforced. Caution must be observed, however, due to recent apprehensions expressed by certain dermatologists concerning possible allergic reactions due to Kathon(R) CG. A multi-centre patch test study is currently being carried out with this preservative in the dermatological clinics of the five Swiss university hospitals.