Bacteria, yeasts and filamentous fungi colonizing immature, mature and senescing primary leaves of field grown Beta vulgaris (sugar beet) were analysed over a complete growing season. Greatest microbial numbers were detected on senescing primary leaves and these numbers increased over most of the season. The number of colonizers detected on mature leaves was found to be stable over most of the study.Filamentous fungi and yeasts were identified to the genus level and the communities found to have greatest diversity during the summer months. There was no consistent pattern of diversity according to leaf type. Two genera of filamentous fungi, Cladosporium and Alternaria and two yeast genera, Cryptococcus and Sporobolomyces were the most numerous fungal populations isolated. Only 8 filamentous fungi and 3 yeast genera were commonly isolated on PDA (potato dextrose agar).Bacterial strains (1236) were isolated on Tryptic Soy Broth (TSB) agar and identified to species, or in some cases sub-species level, by analysis of their fatty acid methyl ester (FAME) profiles. Isolated bacteria were grouped into 78 named and 37 unnamed species clusters. Greatest number of bacterial species were isolated from young plants and leaves, sampled during the autumn months. Bacterial community diversity was lowest in mid-summer and winter months. Pseudomonas was the most commonly isolated genus and Erwinia herbicola the most common species. P. aureofaciens was the only species isolated from soil that was also isolated from the phyllosphere of B. vulgaris throughout the season.

Optically active phosphine ligands, especially C 2 -symmetric diphosphine ligands, have played an important role in various metal-catalyzed asymmetric transformations, and numerous phosphine ligands have been prepared for the development of effective catalytic asymmetric processes. [1] Dramatic results from Knowles and co-workers with the C 2 -symmetric P-chiral ligand 1,2-ethanediylbis[(2-methoxyphenyl)phenylphosphane] (dipamp) for Rh-catalyzed hydrogenations opened up this field of asymmetric catalysis. [2] However, it took nearly two decades for other groups to develop efficient methods to prepare C 2 -symmetric P-chiral diphosphine ligands, largely as a result of the synthetic difficulties in the construction of the P-chiral P centers. [3,4] Nevertheless, some C 2 -symmetric Pchiral diphosphine ligands, such as BisP*, [4a] MiniPhos, [4b] TangPhos, [4c] DiSquareP*, [4d] DuanPhos, [4e] and QuinoxP*, [4f] which exhibit almost perfect enantioselectivity in some Rhcatalyzed asymmetric hydrogenations, have been developed recently. However, a major drawback in many of the requisite synthetic methods (developed by the groups of Imamoto, [3a] JugØ, [3b] Corey, [3c] Evans, [3e] and Livinghouse [3g] ) is that either only one enantiomer of the ligand is readily accessible owing to the nature of the chiral auxiliaries used in the formation of the chiral center or there is a need for tedious diastereomeric derivatization, separation, and deprotection sequences.Ferrocene-based phosphine ligands are well documented. [5] They are more amenable to asymmetric catalysis than many other types of chiral ligands as a result of their easy accessibility and derivatization as well as special electronic and steric properties. Indeed, several families of ferrocenebased phosphine ligands with subtle structural variations have been developed in the last few years. Most of these ligands incorporate both C-centered chirality and planar chirality, and they have proved to be highly effective in numerous asymmetric reactions. In stark contrast, much less attention has been paid to P-chiral phosphines that bear ferrocenyl groups, [3k,l, 5] doubtless as a result of the previous difficulties in their synthesis. Very recently, we reported a highly stereoselective and modular synthesis of ferrocene-based P-chiral phosphine ligands using a simple and straightforward strategy, that is, reaction of a chiral organometallic reagent with a dichlorophosphine, followed by a second organometallic reagent; several families of new ferrocene-based P-chiral phosphine ligands have been developed. [6] Herein, we describe the highly stereoselective synthesis of a new ferrocenebased C 2 -symmetric diphosphine ligand 1 (TriFer). To the best of our knowledge, ligand 1 is the first class of C 2 -symmetric diphosphine that combines C-centered, P-centered, and planar chirality. Most importantly, unprecedented enantioselectivities have been achieved with ligand 1 for the Rhcatalyzed asymmetric hydrogenation of a-substituted cinnamic acids, a class of ver...

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The production of antibacterial compounds by yeasts and yeastlike fungi isolated from the phylloplane is reported. Aureobasidium pullulans, Citeromyces matritensis, Cryptococcus laurentii, Rhodotorula glutinis, and Sporobolomyces roseus produced antibacterial compounds inhibitory to both Pseudomonas fluorescens and Staphylococcus aureus in an overlay bioassay. In contrast, isolates of Candida albicans, Filobasidium uniguttulatum, Saccharomyces cerevisiae, Torulaspora delbruckii, Tremella foliacea, Trichosporon beigelii, and Trichosporon