Combined immunodeficiency due to a mutation in the γ1 subunit of the coat protein I complex.

The coat protein I (COPI) complex mediates retrograde trafficking from the Golgi to the endoplasmic reticulum (ER). Five siblings with persistent bacterial and viral infections and defective humoral and cellular immunity had a homozygous p.K652E mutation in the γ1 subunit of COPI (γ1-COP).

Manganese Uptake, Mediated by SloABC and MntH, Is Essential for the Fitness of Streptococcus mutans.

Early epidemiological studies implicated manganese (Mn) as a possible caries-promoting agent, while laboratory studies have indicated that manganese stimulates the expression of virulence-related factors in the dental pathogen To better understand the importance of manganese homeostasis to pathophysiology, we first used RNA sequencing to obtain the global transcriptional profile of UA159 grown under Mn-restricted conditions. Among the most highly expressed genes were those of the entire operon, encoding a dual iron/manganese transporter, and an uncharacterized gene, here , that codes for a protein bearing strong similarity to Nramp-type transporters. While inactivation of , which encodes the lipoprotein receptor of the SloABC system, or of alone had no major consequence for the overall fitness of , simultaneous inactivation of and (Δ Δ) impaired growth and survival under Mn-restricted conditions, including in human saliva or in the presence of calprotectin.