Kinetic stability as a mechanism for protease longevity

The folding of the extracellular serine protease, α-lytic protease (αLP; EC 3.4.21.12) reveals a novel mechanism for stability that appears to lead to a longer functional lifetime for the protease. For αLP, stability is based not on thermodynamics, but on kinetics. Whereas this has required the coevolution of a pro region to facilitate folding, the result has been the optimization of native-state properties independent of their consequences on thermodynamic stability. Structural and mutational data lead to a model for catalysis of folding in which the pro region binds to a conserved β-hairpin in the αLP C-terminal domain, stabilizing the folding transition state and the native state. The pro region is then proteolytically degraded, leaving the active αLP trapped in a metastable conformation. This metastability appears to be a consequence of pressure to evolve properties of the native state, including a large, highly cooperative barrier to unfolding, and extreme rigidity, that reduce susceptibility to proteolytic degradation. In a test of survival under highly proteolytic conditions, homologous mammalian proteases that have not evolved kinetic stability are much more rapidly degraded than αLP. Kinetic stability as a means to longevity is likely to be a mechanism conserved among the majority of extracellular bacterial pro-proteases and may emerge as a general strategy for intracellular eukaryotic proteases subject to harsh conditions as well.

Longevity and the genetic determination of collagen glycoxidation kinetics in mammalian senescence.

A fundamental question in the basic biology of aging is whether there is a universal aging process. If indeed such a process exists, one would expect that it develops at a higher rate in short- versus long-lived species. We have quantitated pentosidine, a marker of glycoxidative stress in skin collagen from eight mammalian species as a function of age. A curvilinear increase was modeled for all species, and the rate of increase correlated inversely with maximum life-span. Dietary restriction, a potent intervention associated with increased life-span, markedly inhibited glycoxidation rate in the rodent. On the assumption that collagen turnover rate is primarily influenced by the crosslinking due to glycoxidation, these results suggest that there is a progressive age-related deterioration of the process that controls the collagen glycoxidation rate. Thus, the ability to withstand damage due to glycoxidation and the Maillard reaction may be under genetic control.

The ectoparasitic mite Tropilaelaps mercedesae reduces western honey bee, Apis mellifera, longevity and emergence weight, and promotes Deformed wing virus infections

Historically an ectoparasite of the native Giant honey bee Apis dorsata, the mite Tropilaelaps mercedesae has switched hosts to the introduced western honey bee Apis mellifera throughout much of Asia. Few data regarding lethal and sub-lethal effects of T. mercedesae on A. mellifera exist, despite its similarity to the devastating mite Varroa destructor. Here we artificially infested worker brood of A. mellifera with T. mercedesae to investigate lethal (longevity) and sub-lethal (emergence weight, Deformed wing virus (DWV) levels and clinical symptoms of DWV) effects of the mite on its new host. The data show that T. mercedesae infestation significantly reduced host longevity and emergence weight, and promoted both DWV levels and associated clinical symptoms. Our results suggest that T. mercedesae is a potentially important parasite to the economically important A. mellifera honey bee.

Patterns of Stem Cell Divisions Contribute to Plant Longevity

The lifespan of plants ranges from a few weeks in annuals to thousands of years in trees. It is hard to explain such extreme longevity considering that DNA replication errors inevitably cause mutations. Without purging through meiotic recombination, the accumulation of somatic mutations will eventually result in mutational meltdown, a phenomenon known as Muller’s ratchet. Nevertheless, the lifespan of trees is limited more often by incidental disease or structural damage than by genetic aging. The key determinants of tree architecture are the axillary meristems, which form in the axils of leaves and grow out to form branches. The number of branches is low in annual plants, but in perennial plants iterative branching can result in thousands of terminal branches. Here, we use stem cell ablation and quantitative cell-lineage analysis to show that axillary meristems are set aside early, analogous to the metazoan germline. While neighboring cells divide vigorously, axillary meristem precursors maintain a quiescent state, with only 7–9 cell divisions occurring between the apical and axillary meristem. During iterative branching, the number of branches increases exponentially, while the number of cell divisions increases linearly. Moreover, computational modeling shows that stem cell arrangement and positioning of axillary meristems distribute somatic mutations around the main shoot, preventing their fixation and maximizing genetic heterogeneity. These features slow down Muller’s ratchet and thereby extend lifespan.

Soybeans for health, longevity, and economy,

Edition for 1973 published under title: Soybeans for health and a longer life.

Local records; or, Historical register of remarkable events which have occurred in Northumberland and Durham, Newcastle-upon-Tyne, and Berwick-upon-Tweed, with biographical notices of deceased persons of talent, eccentricity, and longevity;

A compilation of similar character, bearing a title almost identical, was made by J. Latimer, covering the period from Oct. 8, 1832, to Aug. 10, 1857.

Modern Methuselahs; or, Short biographical sketches of a few advanced nonagenarians or actual centenarians who were distinguished in art, science, literature, or philanthropy. Also, brief notices of some individuals remarkable chiefly for their longevity.

Introduction.--"Long-lasting."--St. Anthony the Great.-- Joannes Cantacuzenus, emperor of the East.--George Gemisthus Pletho.--Luigi Cornaro.--Titian.--Fontenelle.--Thomas Amory.--A group of far-advanced nonagenarians.--Eva Maria Garrick.--Caroline Lucretia Herschel.--Mary Somerville.--Sir Moses Montefiore.--Martin Joseph Routh.--Mr. Thoms' investigated case of centenarianism.--A group of unquestionable centenarians.--A few recent and probable cases of centenarianism.--Conclusion.

Health and longevity through rational diet; practical hints in regard to food and the usefulness or harmful effects of the various articles of diet.

Includes tables.

On regimen and longevity: comprising materia alimentaria, national dietetic usages, and the influence of civilization on health and the duration of life.

Mode of access: Internet.

Grevillea.

Editor: 1872- , M. C. Cooke.

The duration of life and conditions associated with longevity. A study of the Hyde genealogy,

Mode of access: Internet.

Laboratory studies on the development, longevity, and fecundity of six Lepidopterous pests of cotton in Arizona /

Bibliography: p. 72-73.

Local records; or, Historical register of remarkable events, which have occurred in Northumberland and Durham, Newcastle upon Tyne, and Berwick upon Tweed, from the earliest period of authentic record, to the present time; with biographical notices of deceased persons of talent, eccentricity, and longevity.

For continuation to 1857 see Latimer, John, Local records.

The effects of arts, trades, and professions : and of civic states and habits of living, on health and longevity: with suggestions for the removal of many of the agents which produce disease, and shorten and duration of life /

Advertisements: 16 p. of first group and 2 p. at end.