The cupric complexes of glycine and of alanine

The following report is the first of a projected series of studies of the physical chemistry of the compounds of the heavy metals, particularly of copper and of iron, with substances of biological importance. These studies are invited by the accumulation in recent years of examples of the importance of the heavy metals in biological chemistry

Earth Observing System. Volume 1, Part 2: Science and Mission Requirements. Working Group Report Appendix

Areas of global hydrologic cycles, global biogeochemical cycles geophysical processes are addressed including biological oceanography, inland aquatic resources, land biology, tropospheric chemistry, oceanic transport, polar glaciology, sea ice and atmospheric chemistry

Lithiation of 4-membered heterocycles as useful strategy for the preparation of new molecular scaffolds: addressing the regioselectivity in azetidines and thietanes

Four-membered heterocycles (4-MH) with one or two heteroatoms are of great importance in medicinal chemistry and synthetic organic chemistry. This kind of scaffolds show peculiar structural features, related to the ring “puckering”, and biological properties. Our recent research efforts have been focused on the stereoselective synthesis and functionalization of some 4-MH such as azetidines, thietanes and oxazetidines

Extreme enrichment in atmospheric 15N15N.

Molecular nitrogen (N2) comprises three-quarters of Earth's atmosphere and significant portions of other planetary atmospheres. We report a 19 per mil (‰) excess of 15N15N in air relative to a random distribution of nitrogen isotopes, an enrichment that is 10 times larger than what isotopic equilibration in the atmosphere allows. Biological experiments show that the main sources and sinks of N2 yield much smaller proportions of 15N15N in N2. Electrical discharge experiments, however, establish 15N15N excesses of up to +23‰. We argue that 15N15N accumulates in the atmosphere because of gas-phase chemistry in the thermosphere (>100 km altitude) on time scales comparable to those of biological cycling. The atmospheric 15N15N excess therefore reflects a planetary-scale balance of biogeochemical and atmospheric nitrogen chemistry, one that may also exist on other planets

Where Do You Get Your Protein? Or: Biochemical Realization

Biochemical kinds such as proteins pose interesting problems for philosophers of science, as they can be studied from the points of view of both biology and chemistry. The relationship between the biological functions of biochemical kinds and the microstructures that they are related to is the key question. This leads us to a more general discussion about ontological reductionism, microstructuralism, and multiple realization at the biology-chemistry interface. On the face of it, biochemical kinds seem to pose a challenge for ontological reductionism and hence motivate a dual theory of chemical and biological kinds, a type of pluralism about natural kinds. But it will be argued that the challenge, which is based on multiple realization, can be addressed. The upshot is that there are reasonable prospects for ontological reductionism about biochemical kinds, which corroborates natural kind monism

Interdisciplinary Research-Based Learning in Organic Chemistry and Microbiology Laboratories: Synthesis and Biological Testing of Novel Penicillin Derivatives

Interests in the mechanism that penicillin bestows on its target protein has driven the curiosity of its binding specificity towards the methicillin resistant strain of Staphylococcus areus, and its expression of a unique penicillin binding protein that has enabled its resistance. The ability of bacteria to gain antibiotic resistance has strengthened the ongoing need to synthesize and discover novel drugs to combat the diseases that follow infection. If it were not for the collaborations between scientific disciplines, the production of effective novel drugs such as penicillin would not be the same. To encourage undergraduate students to make real world connections across disciplines, the development of an interdisciplinary organic chemistry-microbiology laboratory experiment was developed. By utilizing discovery-based, authentic research to intentionally encourage student collaboration and improve retention of knowledge gained, a pedagogical experiment involving students from both organic chemistry and microbiology was designed to meet these goals. To implement this educational experiment into existing curriculum, an original experiment was designed and tested in the fall of 2014 to develop a synthetic experimental procedure and biological assay that could be used by organic chemistry and microbiology students in the following spring. The synthetic experimental portion had to be completed within a three-hour laboratory period, yet provide enough versatility for each set of students to synthesize different penicillin compounds by varying the acyl tails attached to the penicillin head group. Once the penicillin compounds were synthesized, the organic chemistry students prepared brief presentations to explain the chemistry behind their syntheses to the microbiology students, who aided in their biological testing, allowing students to visualize the antimicrobial efficacy of their antibiotic on bacterial strains. Microbiology students collaborated in the biological analysis by teaching the chemistry students how to perform a disc diffusion assay and interpret possible susceptibility that the antibiotics may have had on gram-negative and gram-positive bacterial strains. This experiment illustrated the benefits of performing open-ended research to create new possible antibiotics in a chemistry course and of testing the synthesized products in a biology course to visualize the antimicrobial efficacy of their antibiotic on bacterial strains. Overall, this experiment gave students in each course the chance to teach and share their newly learned expertise with their peers, to make scientific connections across disciplines and to address an authentic, open-ended research problem through cooperative learning

Nitrogen Chemistry Significant to Primordial Systems Semiannual Report, 1 Jul. - 31 Dec. 1966

Deoxygenation of benzoyl cyanide, studies of vinyl nitrenes and diene isocyanates, and other aspects of nitrogen chemistry significant to primordial biological system

The Interplay between Chemistry and Mechanics in the Transduction of a Mechanical Signal into a Biochemical Function

There are many processes in biology in which mechanical forces are generated. Force-bearing networks can transduce locally developed mechanical signals very extensively over different parts of the cell or tissues. In this article we conduct an overview of this kind of mechanical transduction, focusing in particular on the multiple layers of complexity displayed by the mechanisms that control and trigger the conversion of a mechanical signal into a biochemical function. Single molecule methodologies, through their capability to introduce the force in studies of biological processes in which mechanical stresses are developed, are unveiling subtle intertwining mechanisms between chemistry and mechanics and in particular are revealing how chemistry can control mechanics. The possibility that chemistry interplays with mechanics should be always considered in biochemical studies.Comment: 50 pages, 18 figure