Variations in the energy metabolism of biotechnologically relevant heterofermentative lactic acid bacteria during growth on sugars and organic acids.

Heterofermentative lactic acid bacteria (LAB) such as Leuconostoc, Oenococcus, and Lactobacillus strains ferment pentoses by the phosphoketolase pathway. The extra NAD(P)H, which is produced during growth on hexoses, is transferred to acetyl-CoA, yielding ethanol. Ethanol fermentation represents the limiting step in hexose fermentation, therefore, part of the extra NAD(P)H is used to produce erythritol and glycerol. Fructose, pyruvate, citrate, and O2 can be used in addition as external electron acceptors for NAD(P)H reoxidation. Use of the external acceptors increases the growth rate of the bacteria. The bacteria are also able to ferment organic acids like malate, pyruvate, and citrate. Malolactic fermentation generates a proton potential by substrate transport. Pyruvate fermentation sustains growth by pyruvate disproportionation involving pyruvate dehydrogenase. Citrate is fermented in the presence of an additional electron donor to acetate and lactate. Thus, heterofermentative LAB are able to use a variety of unusual fermentation reactions in addition to classical heterofermentation. Most of the reactions are significant for food biotechnology/microbiology.

[Psychotherapeutic intervention with families after multiple suicides]. / Mehrfachsuizide als Argument für Postvention.

Every suicide must be seen as tragedy. The amount of that tragedy is sometimes extraordinary. For example, when families experience multiple suicides. The consequences should be, by enhanced postvention to prevent a PTSD-like syndrome and to consider more often the administration of SSRI in persons bereaved by suicide. When manifest phases are prevalent, substances like lithium are recommendable. The importance of psychotherapy and psychosocial intervention has to be emphasized.