蛋白质的边缘稳定性与进化的关系－有意思

为什么蛋白质是边缘稳定的？以下是一篇文章的Ａbstract:
Most globular proteins are marginally
stable regardless of size or activity. The most
common interpretation is that proteins must be
marginally stable in order to function, and so marginal
stability represents the results of positive
selection. We consider the issue of marginal stability
directly using model proteins and the dynamical
aspects of protein evolution in populations. We find
that the marginal stability of proteins is aninherent
property of proteins due to the high dimensionality
of the sequence space, without regard to protein
function. In this way, marginal stability can result
from neutral, non-adaptive evolution. By allowing
evolving protein sub-populations with different stability
requirements for functionality to complete,
we find that marginally stable populations of proteins
tend to dominate. Our results show that functionalities
consistent with marginal stability have a
strong evolutionary advantage, and might arise because
of the natural tendency of proteins towards
marginal stability.
由于自己水平所限，小弟实在不知道marginal stability该怎么翻译，只好照字面意思直译了，还请各位高人指教。（不要笑话我，我刚接触蛋白质技术不久，以前是学医的而非生化专业的）
本文好象也以木村进化论为基石，希望主任和各位高手帮忙解释文中的几个概念：“Panglossian paradigm和sequence entropy“