MGMT: a personal perspective

This review describes the history of studies on alkylation damage of mammalian genomes and its carcinogenic consequences that led to the discovery of a unique DNA repair protein, named MGMT. MGMT repairs O(6)-alkylguanine, a critical mutagenic lesion induced by alkylating agents. The follow-up studies in mammalian cells following the discovery of the ubiquitous repair protein in E. coli are summarized.     

Discovery of plastoquinones: a personal perspective

The discovery and the rediscovery of plastoquinone (PQ) are described together with the definition of its structure as a 2,3-dimethyl 5 solanosyl benzoquinone. The discovery, by M. Kofler, was a result of a search for Vitamin K. Its rediscovery was made by me, when I was at The Enzyme Institute of the University of Wisconsin, analyzing animals and plants for the newly discovered coenzyme Q. In green plants, I found another lipophilic quinone in addition to coenzyme Q. Some misleading evidence suggested as if the new quinone had coenzyme Q activity in mitochondria, but improved methods gave negative results. When I found that the quinone was concentrated in chloroplasts, I considered a role for it in photosynthesis analogous to the role of coenzyme Q in mitochondria. After moving to the Chemistry Department, University of Texas at Austin, I used a plain light bulb and some spinach chloroplasts to show that PQ could be involved in photosynthetic redox reactions. This effect was supported by Norman Bishop’s restoration of chloroplast electron transport after solvent extraction, with PQ and photoreduction studies by E. R. Redfern and J. Friend in R. A. Morton’s laboratory in Liverpool, UK. We also found an additional analog of PQ in addition to a second analog found in Wisconsin. We called the new analogs PQB and PQC. Although we found some restoration effects with PQC, the discovery by W. T. Griffiths in Morton’s laboratory, that PQB and PQC consisted of six forms of PQ each, made it more likely that the new analogs were breakdown products. Morton’s group established the structure of the PQCs as a series of PQs, with a hydroxyl group on the prenyl side chain, and the PQB series as having fatty acids esterified to the hydroxyl groups of PQC. Possible functions of the analogs are also discussed in this article.     

BioMetals: a historical and personal perspective

Understanding of BioMetals developed basically from a starting point about 60 years ago to current mechanistic understanding of the biological behavior of many metal ions from protein structural and functional studies. Figure 1 shows a Biochemical Periodic Table, element by element, with requirements, roles and biochemistry of the specific ions indicated. With few exceptions, the biology is of the ions formed and not of the elemental state of each. Early BioMetals efforts defined nutritional growth needs for animals, plants and microbes for inorganic “macro-nutrients” such as magnesium, calcium, potassium, sodium, and phosphate and of “micronutrients” such as copper, iron, manganese and zinc. Surprises came early with regard to microbes, for example the finding that Escherichia coli (then and now the standard microbial model) grows happily in the apparent total absence of calcium, sodium, and chloride, which are certainly major animal nutrients. Some elements such as mercury and arsenic are never required by living cells, but are always toxic, often at very low levels. Therefore, the division into nutrient elements and toxic elements came soon. For most inorganic nutrients, excessive amounts can be toxic as well, for example for copper and iron.     

The future of ECVAM: a personal perspective

Progress made in the practical application of the validation process is summarised, and some of the remaining problems are considered. Highlights of the first ten years of ECVAM are reviewed, andECVAM's activities as a route of communication on the Three Rs are discussed. Finally, some suggestions are made for maintaining ECVAM's momentum in the future, especially in relation to the challenge and opportunity for alternative methods afforded by the new EU Chemicals Policy.     

Studies in solid-phase peptide synthesis: a personal perspective

By the early 1970s it had became apparent that the solid-phase synthesis of ribonuclease A could not be generalized. Consequently, virtually every aspect of solid-phase peptide synthesis (SPPS) was reexamined and improved during the decade of the 1970s. The sensitive detection and elimination of possible side reactions (amino acid insertion, N(alpha)-trifluoroacetylation, N(alphaepsilon)-alkylation) were examined. The quantitation of coupling efficiency in SPPS as a function of chain length was studied. A new and improved support for SPPS, the "PAM-resin," was prepared and evaluated. These and many other studies from the Merrifield laboratory and elsewhere increased the general acceptance of SPPS leading to the 1984 Nobel Prize in Chemistry for Bruce Merrifield.     

Regulatory enzymes of phosphatidylcholine biosynthesis: a personal perspective

Phosphatidylcholine is a prominent constituent of eukaryotic and some prokaryotic membranes. This Perspective focuses on the two enzymes that regulate its biosynthesis, choline kinase and CTP:phosphocholine cytidylyltransferase. These enzymes are discussed with respect to their molecular properties, isoforms, enzymatic activities, and structures, and the possible molecular mechanisms by which they participate in regulation of phosphatidylcholine levels in the cell.     

Deciphering the RNA polymerase II structure: a personal perspective

This year's Nobel laureate in chemistry is Roger Kornberg. Patrick Cramer gives a personal account of how the Kornberg laboratory determined the structure of the RNA polymerase II core enzyme.     

The current state of personal training: an industry perspective of personal trainers in a small Southeast community

Although research has identified a number of qualities and competencies necessary to be an effective exercise leader, the fitness industry itself is largely unregulated and lacks a unified governing body. As such, a plethora of personal trainer certifications exists with varying degrees of validity that fail to ensure qualified trainers and, therefore, protect the consumer. It is argued that the potential consequences of this lack of regulation are poor societal exercise adherence, potential injury to the client, and poor public perception of personal trainers. Additionally, it is not known whether personal trainers are meeting the needs of their clients or what criteria are used in the hiring of personal trainers. Thus, the purpose of this investigation was to examine the current state of personal training in a midsized Southeast city by using focus group methodology. Local personal trainers were recruited for the focus groups (n = 11), and the results from which were transcribed, coded, and analyzed for themes using inductive reasoning by the authors. Qualities and characteristics that identified by participants clustered around 4 main themes. Client selection rationale consisted of qualities that influenced a client's decision to hire a particular trainer (e.g., physique, gender, race). Client loyalty referred to the particular qualities involved in maintaining clients (e.g., motivation skills, empathy, social skills). Credentials referred to formal training (e.g., college education, certifications). Negative characteristics referred to qualities considered unethical or unprofessional (e.g., sexual comments, misuse of power) as well as the consequences of those behaviors (e.g., loss of clients, potential for litigation). These results are discussed regarding the implications concerning college programs, certification organizations, increasing public awareness of expectations of qualified trainers, and a move towards state licensure.     

Review. The changing face of kuru: a personal perspective

The epidemic of kuru is now known to have been transmitted among the Fore by ritual consumption of infected organs from deceased relatives. As cannibalism was suppressed by government patrol officers during the 1950s, most transmission had ceased by 1957, when the kuru research programme first commenced. As predicted in the 1960s, the epidemic has waned, with progressive ageing of kuru-affected cohorts over the years to 2007. The few cases seen in the twenty-first century, with the longest incubation periods, were almost certainly exposed as children prior to 1960. Although the research programme had almost no role in bringing the kuru epidemic to an end, it did provide important knowledge that was to help the wider world in controlling the later epidemics of iatrogenic and variant Creutzfeldt-Jakob disease and bovine spongiform encephalopathy.     

The development and evaluation of in vitro alternative assays: a personal perspective

Over the past 30 years, FRAME has actively participated in the development, evaluation and validation of in vitro alternative methods through the FRAME Alternatives Laboratory (FAL) in the University of Nottingham Medical School. Much has been learned through collaboration with industry (especially the cosmetics industry), other organisations (especially ECVAM), and certain individuals (notably Dr Bj?rn Ekwall), particularly in relation to the need to use human cell cultures and to obtain, wherever possible, high-quality human data for use in in vivo/in vitro comparisons. Reference is made to the author's experience as Director of the FAL, notably in the development of in vitro assays for basal cytotoxicity, phototoxicity and the effects of repeated dosage.