High-affinity vanadate transport systems have not heretofore been identified in any organism. Anabaena variabilis, which can fix nitrogen by using an alternative V-dependent nitrogenase, transported vanadate well. The concentration of vanadate giving half-maximum V-nitrogenase activity when added to V-starved cells was about 3 x 10(-9) M. The genes for an ABC-type vanadate transport system, vup...

© 2012 The Authors. doi: 10.2340/00015555-1436 Journal Compilation © 2012 Acta Dermato-Venereologica. ISSN 0001-5555 Erythrokeratodermia variabilis (EKV, MIM: 133200) is a rare autosomal dominant disorder characterized by the association of: (i) localized or generalized hyperkeratosis, and (ii) transient erythematous areas (1). Hyperkeratotic areas show well-demarcated, geographically outlined,...

Morphological and morphometric analyses were conducted on the genus Paratylenchus, based on documented data in the literature and characters of Iranian populations of twelve species, including P. arculatus, P. colinus, P. conicephalus, P. coronatus, P. neoamblycephalus, P. neoprojectus, P. obtusicaudatus, P. paraperaticus, P. similis, P. straeleni, P. variabilis and P. veruculatus. Moreover, ma...

The island of Martha's Vineyard, Massachusetts, is the site of a sustained outbreak of tularemia due to Francisella tularensis tularensis. Dog ticks, Dermacentor variabilis, appear to be critical in the perpetuation of the agent there. Tularemia has long been characterized as an agent of natural focality, stably persisting in characteristic sites of transmission, but this suggestion has never b...

The viviparous Great Barrier Reef sponge Luffariella variabilis (Poléjaeff 1884) contains a range of secondary metabolites, including manoalide (1) and manoalide monoacetate (3). ESI (+) FTICR-MS accurate mass determination has, for the first time, been used to detected the presence of 3 only in an organic extract of a single L. variabilis larva showing that the parentally produced 3 is sequest...

JACI MENDES VIEIRA1, RANYSE B. QUERINO2, FERNANDO L. CÔNSOLI1 & ROBERTO A. ZUCCHI1 1Departamento de Entomologia e Acarologia, ESALQ, Universidade de São Paulo, Caixa Postal 9, 13418-900 Piracicaba, SP, Brazil. E-mail: [email protected]; [email protected]; [email protected] 2Empresa Brasileira de Pesquisa Agropecuária, Embrapa Meio-Norte, 64006-220 Teresina, Piauí, Brazil. E-mail: ranyse.silv...

The nitrogenase gene cluster in cyanobacteria has been thought to comprise multiple operons; however, in Anabaena variabilis, the promoter for the first gene in the cluster, nifB1, appeared to be the primary promoter for the entire nif cluster. The structural genes nifHDK1 were the most abundant transcripts; however, their abundance was not controlled by an independent nifH1 promoter, but rathe...

Sessile organisms that live in consolidated substrates frequently compete for space. Coral species have many strategies to face this competition, including harming their opponents or hindering their growth. In the present study, the competitive interactions between three species of zoanthids were investigated in the intertidal zone of a sandstone reef environment in northeastern Brazil. The com...

Anabaena variabilis ATCC 29413 is a filamentous, heterocyst-forming cyanobacterium that has served as a model organism, with an extensive literature extending over 40 years. The strain has three distinct nitrogenases that function under different environmental conditions and is capable of photoautotrophic growth in the light and true heterotrophic growth in the dark using fructose as both carbo...