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River runoff and atmospheric fallout (dust and air particulate matter) are major input sources of natural and anthropogenic terrestrial organic and inorganic components to the Arabian seas. In this study, we report on the various lipid tracer compounds that might be transported to the Arabian Gulf by rivers, dust, and air particulate matter. These are based on geochemical analysis of sediment, dust, and particulate samples collected from Iraq, Kuwait, and Saudi Arabia. The samples were extracted with a dichloromethane/methanol mixture and analyzed by gas chromatography-mass spectrometry. The extractable organic compounds (lipids) in the samples include n-alkanes, n-alkanoic acids, n-alkanols, methyl n-alkanoates, steroids, triterpenoids, carbohydrates, and petroleum hydrocarbons. The steroids and triterpenoids were major components in river and wetland samples. The major sources of these lipids were from natural vegetation, microbial (plankton and bacteria) residues in the sediments, sand, and soils, with some contribution from anthropogenic sources. Accordingly, these sources could be major inputs to the Arabian seas besides the autochthonous marine products. Future studies of the organic and inorganic biogeochemistry on river, dust, and coastal areas are needed to characterize the various regional sources, transformation, and diagenetic processes of the organic matter en route to the marine environment.

An actinomycete, strain 8T, was isolated from marsh soil in Kuwait. The strain was aerobic, gram-positive, halophilic and produced light blue to greyish aerial mycelium. The warty spores were sessile, occurring singly or in pairs on aerial mycelium. The mycelium was stable and did not fragment during ageing. Chemotaxonomic markers of the isolate were consistent with its classification as Saccharomonospora. The strain possessed meso-diaminopimelic acid as the diagnostic amino acid in the peptidoglycan. The diagnostic sugars were arabinose and galactose; polar lipids were phosphatidyl inositol, phosphatidyl ethanolamine, hydroxy-phosphatidyl ethanolamine, lyso-phosphatidyl ethanolamine and diphosphatidyl glycerol; the principal menaquinone was MK-9(H4); and the iso/anteiso-branched fatty acid pattern was combined with 10-methyl-branched and 2-hydroxy-branched fatty acids. Saccharomonospora cyanea DSM 44106T was the closest phylogenetic neighbour of strain 8T, showing 96.8% 16S rDNA sequence similarity. These data, together with distinct physiological traits, led to the conclusion that the novel isolate represents a new species within the genus Saccharomonospora for which the name Saccharomonospora halophila sp. nov. is proposed. The type strain is strain 8T (= DSM 44411T =NRRL B-24125T).

A polyphasic taxonomic study of a halotolerant micro-organism, isolated from Kuwait salt marsh soil, revealed that this strain represents a novel Nocardiopsis species. The strain produced substrate and aerial mycelium, grew at 28-35 degrees C in salt concentrations of 0-15% and was slightly keratinolytic. Results of the 165 rDNA sequence comparison revealed that strain F100T clustered with strains of the genus Nocardiopsis. This is consistent with other data such as: (i) growth characteristics, i.e. the formation of a white to yellow aerial mycelium and the typical zig-zag form of hyphae, which fragment when ageing; (ii) the presence of DL-diaminopimelic acid and glucose plus ribose in whole-cell hydrolysates; (iii) the presence of phosphatidyl choline, phosphatidyl inositol, phosphatidyl glycerol, phosphatidyl methylethanolamine and diphosphatidyl glycerol in polar lipid extracts; (iv) the presence of menaquinones MK-10(H(0-6)) and MK-11(H(0-6)) in the non-polar fraction; (v) the presence of iso/anteiso-branched plus 10-methyl-branched fatty acids, showing the diagnostic combination for Nocardiopsis spp. of 14-methyl-hexadecanoic acid (18%), oleic acid (9%) and tuberculostearic acid (2%); and (v) the absence of mycolic acids. Analysis of 16S rDNA revealed that strain F100T represents a distinct taxon within Nocardiopsis. Based upon phenotypic differences to other members of the genus, a novel species, Nocardiopsis halotolerans sp. nov., is proposed. The type strain of the species is F100T (= DSM 44410T = NRRL B-24124T).

Advances in microbial enzyme technology, keratinolytic proteases in this case, offer considerable opportunities for a low-energy consuming technology for bioconversion of poultry feathers from a potent pollutant to a nutritionally upgraded protein-rich feedstuff for livestock. A compendium of recent information on microbial keratinolysis in nature and infection (dermatophytoses) has been provided as underscoring feasible harnessing of the biotechnology for nutritional improvement of feathers, and as an alternative to conventional hydrothermal processing. Supporting evidence of a nutritional (amino acid) upgrading sequel to diverse microbial treatments of feathers, and positive results obtained from growth studies in rats and chicks have been presented. The paper concludes with suggestions for avenues of application of biotechnology for nutritional improvement of feather (and other keratins) as feedstuffs for livestock

Fine particles in the atmosphere from soil and sand resuspension contain a variety of organic compounds from natural biogenic and anthropogenic matter. Soil and sand samples from various sites near Kuwait city were collected, sieved to retain the fine particles, and extracted with a mixture of dichloromethane and methanol. The extracts were derivatized and analyzed by gas chromatography-mass spectrometry in order to characterize the chemical compositions and sources of the organic components. The major inputs of organic compounds were from both natural biogenic and anthropogenic sources in these samples. Vegetation was the major natural source of organic compounds and included n-alkanols, n-alkanoic acids, n-alkanes, sterols and triterpenoids. Saccharides had high concentrations (31–43%) in the sand dune and seafront samples, indicating sources from decomposed vegation materials and/or the presence of viable microbiota such as bacteria and fungi. Vehicular emission products, leakage of lubricating oils, discarded plastics and emissions from cooking operations were the major anthropogenic inputs in the samples from the urban areas. This input was mainly UCM, n-alkanes, hopanes, plasticizers and cholesterol, respectively.

Keratinolytic potential of A. keratinophila (DSM 44409T), a newly described Amycolatopsis sp. isolated from cultivated soil in Kuwait, was demonstrated using keratinazure as the sole source of carbon and nitrogen as estimated by gel diffusion assay. Effects of 12 various nutritional supplements on the keratinolytic and azocollytic activities were determined. NH4H2PO4 and KNO3 in the medium supported a significantly higher keratinolytic activity than other supplements. However, azocollytic activities in all the supplemented media and the control were same. Best combination of carbon and nitrogen supplements (galactose and NH4H2PO4 respectively) used to evaluate the dynamics of growth and enzymes (keratinase and protease) activities of the isolate revealed a luxuriant growth with optimal keratinolytic activity occurring during the log phase. Other parameters of the fermentation medium, including pH, biomass accumulation, total protein and free amino acid concentrations were also studied.

From several soil samples screened for the occurrence of keratinolytic fungi, soils cultivated with ornamental plants were found to contain strains of the dermatophytic fungus Microsporum gypseum. One soil sample was dominated by this species.

A keratinolytic, nocardioform actinomycete, strain D2(T), was isolated from Kuwait marsh soil by the bait technique using animal wool. Strain D2(T) was an aerobic, Gram-positive organism that produced light-grey aerial mycelium but no specific spore chains. 16S rDNA sequence analyses and chemotaxonomic markers were consistent with the classification of strain D2(T) in the genus Amycolatopsis, i.e. it had meso-diaminopimelic acid in its peptidoglycan, arabinose and galactose as its diagnostic sugars, the polar lipids phosphatidylinositol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine and diphosphatidylglycerol, menaquinone MK-9(H4) and an iso-/anteiso-branched fatty acid pattern combined with 10-methyl-branched and 2-hydroxy-branched fatty acids. Amycolatopsis japonica was the closest phylogenetic neighbour of strain D2(T), showing 99.4% 16S rDNA sequence similarity with the novel strain. A. japonica and strain D2(T) could be clearly separated from each other on the basis of their low DNA-DNA reassociation value (55.9%). These data, together with its distinct physiological traits, led to the conclusion that strain D2(T) represented a novel species within the genus Amycolatopsis, for which the name Amycolatopsis keratiniphila (type strain D2(T) = DSM 44409(T) = NRRL B24117(T)) is proposed.

A total of 28 L-rhamnose-negative mutants in Salmonella typhimurium LT2 were all linked by P22 transduction and were classified into five groups on the basis of genetic and biochemical experiments. Deletion mapping showed that the gene order was rhaD rhaA rhaB rhaC rhaT . rhaA mutants lacked an inducible L-rhamnose isomerase, rhaB mutants lacked an inducible L- rhamnulokinase , and rhaD mutants were probably defective in L- rhamnulose -1-phosphate aldolase. Mutants that were unable to accumulate L-[14C]rhamnose but could grow on 1% L-rhamnose were designated rhaT to indicate a defect in L-rhamnose transport. Genetic evidence supports the hypothesis that the rhaC gene is a positive regulator of rha gene expression. (i) Pleiotropically negative mutants in the rhaC gene were isolated at a high frequency. (ii) Mutants containing an insertion or deletion within the rhaC gene had a pleiotropically negative phenotype. (iii) Complementation tests indicated that rhaC + was dominant to rhaC -. (iv) Rha+ revertants of deletion and Tn10 insertion mutations in the rhaC gene were isolated.

Six L-arabinose transport-deficient mutants of Salmonella typhimurium LT2 were isolated on the basis of their inability to ferment low concentrations of L-arabinose. The mutations were localized between serA and lys on the S. typhimurium genetic map and assigned to the araE locus. An araE-lac fusion strain was constructed and used to determine that the direction of araE transcription was counterclockwise on the S. typhimurium genetic map. beta-Galactosidase activity was induced by L-arabinose in the araE-lac fusion strain, suggesting that araE expression is controlled at the level of transcription.