Alternate quinone coupling in a new class of succinate dehydrogenase may potentiate mycobacterial respiratory control.

There is a paucity of information on the unique components that pathogens use to form respiratory chains. It is not known why mycobacteria encode multiple succinate dehydrogenases (SDHs) to perform menaquinone-linked succinate oxidation, a thermodynamically unfavorable reaction (ΔG° = +21 kJ·mol ). In other bacteria, specific di-heme SDHs overcome this using the proton motive force.

Variation in female grey seal (Halichoerus grypus) reproductive performance correlates to proactive-reactive behavioural types.

Consistent individual differences (CIDs) in behaviour, indicative of behavioural types or personalities, have been shown in taxa ranging from Cnidaria to Mammalia. However, despite numerous theoretical explanations there remains limited empirical evidence for selective mechanisms that maintain such variation within natural populations. We examined behavioural types and fitness proxies in wild female grey seals at the North Rona breeding colony.