For the first time, an updated checklist of Acacia , Senegalia and Vachellia species in Egypt is provided, focusing on the exotic species. Taking into consideration the retypification of genus Acacia ratified at the Melbourne International Botanical Congress (IBC, 2011), a process of reclassification has taken place worldwide in recent years. The review of Acacia and its segregates in Egypt became necessary in light of the available information cited in classical works during the last century. In Egypt, various taxa formerly placed in Acacia s.l ., have been transferred to Acacia s.s ., Acaciella , Senegalia , Parasenegalia and Vachellia . The present study is a contribution towards clarifying the nomenclatural status of all recorded species of Acacia and its segregate genera. This study recorded 144 taxa (125 species and 19 infraspecific taxa). Only 14 taxa (four species and 10 infraspecific taxa) are indigenous to Egypt (included now under Senegalia and Vachellia ). The other 130 taxa had been introduced to Egypt during the last century. Out of the 130 taxa, 79 taxa have been recorded in literature. The focus of this study is the remaining 51 exotic taxa that have been traced as living species in Egyptian gardens or as herbarium specimens in Egyptian herbaria. The studied exotic taxa are accommodated under Acacia s.s. (24 taxa), Senegalia (14 taxa) and Vachellia (13 taxa). Identification keys for the studied genera, generic groups and species have been provided using different taxonomic criteria. For each taxon, the validated name with the first citation followed by relevant Egyptian citations, typification, synonyms, distinctive features, origin, ecology (when available), utilisation and selected specimens are provided. The study revealed the presence of 22 newly recorded taxa in Egypt. Additionally, a list of excluded, unvalidated and unresolved names is given.

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This paper discusses the process of retrieval and updating legacy data to allow on-line discovery and delivery. There are many pitfalls of institutional and non-institutional ecological data conservation over the long term. Interruptions to custodianship, old media, lost knowledge and the continuous evolution of species names makes resurrection of old data challenging. We caution against technological arrogance and emphasise the importance of international standards. We use a case study of a compiled set of continent-wide vegetation survey data for which, although the analyses had been published, the raw data had not. In the original study, publications containing plot data collected from the 1880s onwards had been collected, interpreted, digitised and integrated for the classification of vegetation and analysis of its conservation status across Australia. These compiled data are an extremely valuable national collection that demanded publishing in open, readily accessible online repositories, such as the Terrestrial Ecosystem Research Network (http://www.tern.org.au) and the Atlas of Living Australia (ALA: http://www.ala.org.au), the Australian node of the Global Biodiversity Information Facility (GBIF: http://www.gbif.org). It is hoped that the lessons learnt from this project may trigger a sober review of the value of endangered data, the cost of retrieval and the importance of suitable and timely archiving through the vicissitudes of technological change, so the initial unique collection investment enables multiple re-use in perpetuity.

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Glutamine, in the presence of alpha-oxoglutarate, stimulates nicotinamide nucleotide oxidation by crude extracts of pea roots and leads to a reductant-dependent formation of glutamate. Commercially available asparagine also stimulates nicotinamide nucleotide oxidation in the presence of alpha-oxoglutarate, but the reaction causing the stimulation can occur in the absence of a reductant, is inhibited by transaminase inhibitors, and is additive to the glutamine reaction. The asparagine used was found to be contaminated with aspartate. Repurified asparagine, chromatographically free of aspartate, did not stimulate the rate of nicotinamide nucleotide oxidation, and it is probable that the original stimulation was due to aspartate contamination. It is concluded that pea-root glutamine (amide)-alpha-oxoglutarate aminotransferase (glutamate synthase), in common with the enzyme in leaves, is specific for glutamine as the N donor and alpha-oxoglutarate as the N acceptor. The significance of the enzyme in conjunction with glutamine synthetase in the assimilation of nitrate by roots is discussed.

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