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Phenotypic plasticity – the ability of an individual organism to alter its features in direct response to a change in its environment – is ubiquitous. Understanding how and why this phenomenon exists is crucial because it unites all levels of biological inquiry. This book brings together researchers who approach plasticity from diverse perspectives to explore new ideas and recent findings about the causes and consequences of plasticity. Contributors also discuss such controversial topics as how plasticity shapes ecological and evolutionary processes; whether specific plastic responses can be passed to offspring; and whether plasticity has left an important imprint on the history of life. Importantly, each chapter highlights key questions for future research. Drawing on numerous studies of plasticity in natural populations of plants and animals, this book aims to foster greater appreciation for this important, but frequently misunderstood phenomenon. Key Features Written in an accessible style with numerous illustrations, including many in color Reviews the history of the study of plasticity, including Darwin’s views Most chapters conclude with recommendations for future research

Leishmania sp. belong to the trypanosomatid group of protozoan parasites and are responsible for a wide variety of diseases collectively known as leishmaniasis. They continue to be a major health problem of the world threatening ~ 350 million people, majority of whom are from the impoverished sections of the community. Unavailability of a vaccine and increasing signs of resistance to few existing drugs warrants consolidated effort towards discovery of novel antileishmanial drug targets. In recent times, carbonic anhydrases (CAs) have been studied in a number of pathogenic microorganisms and preliminary evidences suggest that it can be a promising drug target. We discovered that Leishmania major expresses two CAs (LmCAs), namely a β-family LmCA1 and an α-family LmCA2. Our preliminary pharmacological inhibition studies, using an established CA inhibitor, suggested that LmCA activity is important for parasite growth and survival. Coupling pharmacological inhibition data with structural insights obtained from homology model of LmCA1, we arrived at the conclusion that LmCAs, especially LmCA1, is structurally distinct from its human α-CA counterparts. These encouraging results prompted us to investigate the role of LmCA1 in parasite physiology. Subcellular localization studies confirmed that LmCA1 is localized in the cytosol of the parasite. LmCA1-/- knockout strain could not be generated in repeated attempts, suggesting its functional indispensability to the parasite. However, we were able to generate LmCA1+/- heterozygous strain, which grew normally in neutral medium but suffered from intracellular acidosis-induced cell cycle arrest, growth retardation and morphological abnormalities in acidic pH. This strain also showed reduced parasite load and infectivity in macrophage cell line and mice. Thus, LmCA1 is crucial for cytosolic buffering of L. major and plays a determining role in parasite proliferation in acidic milieu in vitro as well as within phagolysosomes of host macrophages. In addition to acid acclimatization, LmCA1 plays an indispensable role in the gluconeogenic pathway of the parasite. Under low glucose stress, LmCA1+/- heterozygous strain suffered from cell cycle arrest, growth retardation and morphological abnormalities. These phenotypes were due to depleted intracellular glucose pool, which ultimately resulted in faulty ATP production in the mutant parasite. Thus, indispensability of LmCA1 in such crucial physiological and metabolic processes of Leishmania highlights LmCA1 as a potential antileishmanial drug target.

Microbiology covers the scope and sequence requirements for a single-semester microbiology course for non-majors. The book presents the core concepts of microbiology with a focus on applications for careers in allied health. The pedagogical features of the text make the material interesting and accessible while maintaining the career-application focus and scientific rigor inherent in the subject matter. Microbiology’s art program enhances students’ understanding of concepts through clear and effective illustrations, diagrams, and photographs. Microbiology is produced through a collaborative publishing agreement between OpenStax and the American Society for Microbiology Press. The book aligns with the curriculum guidelines of the American Society for Microbiology.

Hepatitis B Virus (HBV) is a DNA virus and belongs to the genus Orthohepadnavirus of the Hepadnaviridae family which represents one of two animal viruses with a DNA genome which replicates by reverse transcription of a viral RNA intermediate. Nucleotide variation led to further sub-classification into 8 genotypes (A to H). The reverse transcription step within its life cycle is prone to the introduction of errors and recombination when dually infected. This leads to a viral quasispecies which forms during the course of infection with many minor population variants; such variants can however only be detected by means of ultra-deep sequencing. A recent study in the Department of Medical Virology (UP) by Mayaphi et al. identified a number of the specimens that partitioned away from the typical subgenotype A1 clades with high bootstrap values and longer branch lengths. Thus, the main objective of the current study was to characterize the full genome of all variants for the outliers observed in the aforementioned study, inclusive of potential recombination, dual infection and minor populations. Twenty samples were selected from a previous cohort for purposes of the present study. The viral DNA was extracted and amplified by PCR according to the methods described by Günther et al. with modified primer sets. Nineteen of the samples were successfully amplified and 15 of these were sequenced. Specimens were sequenced by NGS on the Illumina MiSeq™ sequencer and sequence data used to reconstruct the viral quasispecies of each specimen. Further analyses of the reconstructed variants included molecular characterization as well as phylogenetic analysis and screening for recombination and drug resistance mutations. Full genome coverage was obtained for twelve of the fifteen samples and full genome variants reconstructed, generating nearly 40 full genomes. Phylogenetic analysis showed that the majority of the samples are of genotype A, more specifically of subgenotype A1, differing by less than 4% from known sequences. The phylogenetic analysis revealed a similar clade of outliers, where four samples clustered together with significant bootstrap support (75%) and a fifth sample partitioned separate from, yet close to, this clade, away from the typical African A1 clade. This clade was assigned to genogroup III. Three samples were of the Asian A1 clade (genogroup I) with remaining specimens grouping within genotype D and E. The variants showed low diversity within each specimen with some differing at but a few positions across the genome while even the most diverse quasispecies differed by less than a percentage (32 positions). Several unique and atypical positional variations were observed amongst study samples of which some were present in but one of the variants for that sample. Twenty-six lead to shared amino acid changes. Some observed changes, such as A1762T/G1764A and G1896A, could explain the serological patterns such as HBeAg negativity while others, such as C2002T, were previously implicated in disease progression and severity. Sample N199 presented a longer branch length and revealed short regions within the genome that display evidence of recombination between HBV/A1 and HBV/A2. The results illustrate the utility of NGS technology in characterizing viral variants.

Anaerobic Reactors is the forth volume in the series Biological Wastewater Treatment. The fundamentals of anaerobic treatment are presented in detail, including its applicability, microbiology, biochemistry and main reactor configurations. Two reactor types are analysed in more detail, namely anaerobic filters and especially UASB (upflow anaerobic sludge blanket) reactors. Particular attention is also devoted to the post-treatment of the effluents from the anaerobic reactors. The book presents in a clear and informative way the main concepts, working principles, expected removal efficiencies, design criteria, design examples, construction aspects and operational guidelines for anaerobic reactors. About the series: The series is based on a highly acclaimed set of best selling textbooks. This international version is comprised by six textbooks giving a state-of-the-art presentation of the science and technology of biological wastewater treatment. Other titles in the series are: Volume 1: Waste Stabilisation Ponds; Volume 2: Basic Principles of Wastewater Treatment; Volume 3: Waste Stabilization Ponds; Volume 5: Activated Sludge and Aerobic Biofilm Reactors; Volume 6: Sludge Treatment and Disposal