Caldwell D E, Caldwell S J
College of Agriculture, University of Saskatchewan, Saskatoon SK, S7N 5A8 Canada.
Microb Ecol. 2004 Apr;47(3):252-65. doi: 10.1007/s00248-003-1015-x. Epub 2004 Mar 25.
Microorganisms continually redefine themselves at many levels, including the molecule, cell, and community. Although it was initially assumed that this resulted from the genesis of information within DNA alone, it has since been shown that innovation originates at multiple levels. This occurs through calculative units, each unit consisting of two proliferating structures, one nested within the other and each undergoing changes in structural geometry that affect the proliferation rate of the other. For example, the recombination of genetic structures affects the proliferation of community structures, and the recombination of community structures affects the proliferation of genetic structures. The proliferation of a nested series of structures (e.g., genes proliferating within cells, cells proliferating within communities, communities proliferating within ecosystems) results in a logic circuit that calculates the form and function of each structural element in the series. In this situation each element functions as both a habitat and an inhabitant (environment and organism), and it is this dichotomy that determines the balance of nature. Nested geological structures, such as minerals and continents, also proliferate and redefine themselves in much the same way. Microbe-mineral interactions thus link nested biological calculations to an analogous set of nested geological calculations. Examples include the microorganisms involved in the nucleation (proliferation) of ferric hydroxides, carbonates, silicates, and ice crystals.
微生物在包括分子、细胞和群落等多个层面不断重新定义自身。尽管最初认为这仅仅是由DNA内信息的产生所致,但后来表明创新源自多个层面。这是通过计算单元发生的,每个单元由两个增殖结构组成,一个嵌套在另一个之中,且每个结构的几何形状都会发生变化,进而影响另一个结构的增殖速率。例如,遗传结构的重组会影响群落结构的增殖,而群落结构的重组会影响遗传结构的增殖。一系列嵌套结构(如基因在细胞内增殖、细胞在群落内增殖、群落在生态系统内增殖)的增殖会形成一个逻辑电路,该电路计算系列中每个结构元素的形式和功能。在这种情况下,每个元素既作为栖息地又作为居住者(环境和生物体)发挥作用,正是这种二分法决定了自然的平衡。嵌套的地质结构,如矿物质和大陆,也以大致相同的方式增殖并重新定义自身。因此,微生物与矿物质的相互作用将嵌套的生物计算与类似的一组嵌套地质计算联系起来。例子包括参与氢氧化铁、碳酸盐、硅酸盐和冰晶成核(增殖)的微生物。