Studies on Resistance to Vegetative (Vip3A) and Crystal (Cry1A) Insecticidal Toxins of Bacillus thuringiensis in Heliothis virescens (Fabricius)

Bacillus thuringiensis (Bt) toxins expressed in commercial transgenic crop varieties are all δ-endotoxins (Cry toxins) but the identification of novel vegetative insecticidal proteins (Vip toxins) has extended the range of insecticidal proteins derived from Bt. One such Vip toxin, Vip3A, primarily targets the midgut epithelium cells of susceptible insects as Cry toxins do, although they appear to have different binding sites. The present study investigated the comparative toxicity of Vip3A, Cry1Ab and Cry1Ac against Heliothis virescens (tobacco budworm) and the impact of antibiotics on Bt insecticidal activity. The selection of a resistant Vip3A population led to the determination of cross-resistance, the genetics of resistance and fitness effects. There was very little variability in the natural susceptibility to Vip3A, Cry1Ab and Cry1Ac in the populations tested, although the toxicity of Vip3A was much lower compared to the Cry1A toxins. A Vip3A resistant population was successfully established within 13 selected generations, with little or no cross-resistance to Cry1Ab or Cry1Ac. The inheritance of resistance ranged from almost completely recessive to incompletely dominant with a possible paternal influence, was polygenic and relatively stable. Vip3A resistance showed a fitness benefit, reduced larval development time, and fitness costs, including survival to adult eclosion, reduced egg viability and reduced male mating success. The effects of antibiotics on H. virescens larval susceptibility to Bt toxins varied depending on antibiotic treatment, the Bt toxin used and the larval instar tested. Bt cotton expressing both Vip3A and Cry1Ab to provide activity against a wide range of pest Lepidoptera, including H. virescens, a major cotton pest in the USA is in the process of commercialisation. The present work will help to support a suitable insecticide resistance management strategy for continued use of Bt toxin in transgenic crops

Book Review: The Responsive Self: Personal Religion in Biblical Literature of the Neo-Babylonian and Persian Periods

In this short, engaging, and learned book, Susan Niditch takes readers into the world of sixth–fifth century BCE Judah/Yehud to understand what it might have meant for religion during this period to have become “personal.” Books like Jeremiah, Ezekiel, Job, Ecclesiastes, Psalms, Proverbs, and Zechariah, among others, take center stage as examples of the turn toward the individual’s relationship to God and the personal psychology of discrete actors in the process of figuring out their place in the world. Though biblical scholars have often correctly emphasized the “group identity” of ancient Israelites, rallying around symbols like temple, land, and king, the era under Niditch’s focus saw many fascinating expressions of a singular person, a “self” in the making, forging an autobiographical relationship to the deity. Not limited purely to biblical texts, Niditch illuminates this phenomenon through the sociological study of religion as well as archaeology. Her simple but convincing argument is that during the exilic and post-exilic periods in Israel authors turned toward complex descriptions of the self, and in doing so ushered in a new period in which religiously creative expressions of personality entered the world of “lived religion” as never before

The Giant in a Thousand Years: Tracing Narratives of Gigantism in the Hebrew Bible and Beyond

This essay is an attempt to organize the Bible’s giants by category and to continue to elevate these figures as a rightful object of scholarly attention

On the Uncertainty of Archive Hydrographic Datasets

As the international hydrographic community continues to address the question of the irreducible uncertainty in modern surveys, we must ask how we do the same with archived Vertical Beam Echosounder (VBES) and leadline datasets. The ONR funded Strataform project surveyed an area of the New Jersey shelf around 39◦12’N 72◦50’W using an EM1000 Multibeam Echosounder (MBES). This area is also covered by NOAA surveys from 1936- 38 (assumed to be leadline) and 1975-76 (VBES). By comparison of the archival soundings to the MBES data, estimates of measurement error for the archival surveys are constructed as a function of depth. The analysis shows that archival leadline smoothsheets are heavily biased in deeper water because of ‘hydrographic rounding’ and may be unrecoverable, but that the VBES data appear approximately unbiased and may be used to construct products compatible with modern surveys. Estimates of uncertainty for a surface model generated from the archive data are then constructed, taking into account measurement, interpolation, and hydrographic uncertainty (addressing the problems of unobserved areas and surface reconstruction stability). Finally, the paper addresses the generality of the method, and its implications for the community’s duty to convey our uncertainty to the end user

Mutagenic and Spectroscopic Investigation of pH Dependent CooA DNA Binding

The carbon monoxide (CO) sensing heme protein, CooA, is a transcription factor which exists in several bacteria that utilize CO as an energy source. CooA positively regulates the expression of coo genes in the presence of CO such that the corresponding proteins may metabolize CO. The present studies have yielded the unexpected result that Fe(III) CooA binds DNA tightly at pH \u3c 7, deviating from all previously reported work which indicate that CooA DNA binding is initiated only when the exogenous CO effector reacts with the Fe(II) CooA heme. This observation suggests that the disruption of one or more salt bridges upon effector binding may be a critical feature of the normal CooA activation mechanism. To test this possibility, several protein variants that eliminated a selected salt bridge for the CooA homolog from Rhodospirillum rubrum were prepared via site-directed mutagenesis. Samples of these variant proteins, which were overexpressed in Escherichia coli, were then characterized by spectroscopic methods and functional assays to investigate the impact these mutations had on CooA heme coordination structure and DNA-binding activity. Results of this work are presented in light of the accepted CooA activation mechanism