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Fatty acid levels in the blood are dynamic and chronic elevation of plasma fatty acid levels is associated with some metabolic disorders such as cardiovascular disease and diabetes. Since the binding of Zn(2+) to albumin is important for the control of circulatory/cellular Zn(2+) dynamics, this relationship is likely to have important physiological and pathological implications. This article is part of a Special Issue entitled Serum Albumin.

Serum albumin is the major zinc carrier in blood plasma. Fatty acid binding to albumin regulates its zinc-binding ability and alters plasma zinc speciation.

Zinc is a recognized essential element for the majority of organisms, and is indispensable for the correct function of hundreds of enzymes and thousands of regulatory proteins. In aquatic photoautotrophs including cyanobacteria, zinc is thought to be required for carbonic anhydrase and alkaline phosphatase, although there is evidence that at least some carbonic anhydrases can be cambialistic, i.e., are able to acquire in vivo and function with different metal cofactors such as Co2+ and Cd2+. Given the global importance of marine phytoplankton, zinc availability in the oceans is likely to have an impact on both carbon and phosphorus cycles. Zinc concentrations in seawater vary over several orders of magnitude, and in the open oceans adopt a nutrient-like profile. Most studies on zinc handling by cyanobacteria have focused on freshwater strains and zinc toxicity; much less information is available on marine strains and zinc limitation. Several systems for zinc homeostasis have been characterized in the freshwater species Synechococcus sp. PCC 7942 and Synechocystis sp. PCC 6803, but little is known about zinc requirements or zinc handling by marine species. Comparative metallo-genomics has begun to explore not only the putative zinc proteome, but also specific protein families predicted to have an involvement in zinc homeostasis, including sensors for excess and limitation (SmtB and its homologs as well as Zur), uptake systems (ZnuABC), putative intracellular zinc chaperones (COG0523) and metallothioneins (BmtA), and efflux pumps (ZiaA and its homologs).

At least one third of all proteins are thought to require a metal ion co-factor for their function. Recognition of the importance of metals in biological systems and major advances in analytical instrumentation and technology have led to the emergence of the new research area of metalloproteomics in recent years. Despite this progress, the experimental determination of in-vivo metal cofactors has remained challenging, because this requires elucidation of protein interactions with non-covalently bound metal ions. This critical review highlights current methodological approaches, focusing, in particular, on issues relating to the fractionation and separation of the metalloproteome, including recent experience with metalloproteomics for marine cyanobacteria in our laboratory. Metalloproteomics promises to deliver novel insights into fundamental biological processes in the future, but it is clear that further methodological advances are necessary to exploit the full potential of this emerging research area.

Seed size was examined as a possible explanation for variation in the size of containerized loblolly pine (Pinustaeda L.) seedlings. Under laboratory conditions of minimal environmental stress, larger seed were found to germinate more quickly and produce a larger germinant after 28 days of growth. In a similar experiment conducted under greenhouse growing conditions, large seed produced the largest seedlings. Size differences among seedlings in both experiments resulted from differences in the rate of germination unique to each seed size class. Consequently, seedling size and possibly uniformity of growth were considered to be a function of germination patterns which were strongly influenced by seed size and weight.

Direct seeding is a potential method for reforestation of pines on many southern sites. The success of direct seeding, however, depends, at least in part, in reducing seed predation by birds and rodents. We conducted a series of tests to assess the efficacy of' capsicum and thiram in reducing mouse damage to longleaf pine (Pinus palustris) seeds. House mice (Mus musculus) predation was reduced (P < 0.05) by treating seeds with either capsicum or thiram or a mixture of the two ingredients. Deer mice (Peromyscus nranicufutus) avoided seeds treated with a mixture of capsicum and thiram. We conclude that the capsicum and thiram mixture should be pursued as a potential repellent to protect longleaf pine seeds from animal predation when these seeds are used in direct seeding efforts to establish southern pine forests.