Making contact away from home: a bacterial secreted effector mediates inter-organelle communication.

Inter-organelle communication via the formation of membrane contact sites (MCS) is essential for cell homeostasis. Bacterial pathogens residing in membrane bound vacuoles have exploited this biological process by secreting effector proteins that establish and function at MCS between their vacuole and host organelles. In this issue of EMBO reports, Angara et al (2024) identify a effector protein, CbEPF1, that uses molecular mimicry of eukaryotic FFAT motifs to alter MCS between two host organelles: the endoplasmic reticulum and lipid droplets.

Critical role of growth medium for detecting drug interactions in Gram-negative bacteria that model responses.

Unlabelled: The rise in infections caused by multidrug-resistant (MDR) bacteria has necessitated a variety of clinical approaches, including the use of antibiotic combinations. Here, we tested the hypothesis that drug-drug interactions vary in different media, and determined which models best predict drug interactions in the lungs. We systematically studied pair-wise antibiotic interactions in three different media, CAMHB, (a rich lab medium standard for antibiotic susceptibility testing), a urine mimetic medium (UMM), and a minimal medium of M9 salts supplemented with glucose and iron (M9Glu) with three Gram-negative ESKAPE pathogens, (Ab), (Kp), and (Pa).

Pathogen vacuole membrane contact sites - close encounters of the fifth kind.

Vesicular trafficking and membrane fusion are well-characterized, versatile, and sophisticated means of 'long range' intracellular protein and lipid delivery. Membrane contact sites (MCS) have been studied in far less detail, but are crucial for 'short range' (10-30 nm) communication between organelles, as well as between pathogen vacuoles and organelles. MCS are specialized in the non-vesicular trafficking of small molecules such as calcium and lipids.

Phosphoregulation accommodates Type III secretion and assembly of a tether of ER- inclusion membrane contact sites.

Membrane contact sites (MCS) are crucial for nonvesicular trafficking-based interorganelle communication. Endoplasmic reticulum (ER)-organelle tethering occurs in part through the interaction of the ER resident protein VAP with FFAT motif-containing proteins. FFAT motifs are characterized by a seven amino acidic core surrounded by acid tracks.

Host and Bacterial Glycolysis during Infection.

The obligate intracellular pathogen is the leading cause of noncongenital blindness and causative agent of the most common sexually transmitted infection of bacterial origin. With a reduced genome, is dependent on its host for survival, in part due to a need for the host cell to compensate for incomplete bacterial metabolic pathways. However, relatively little is known regarding how is able to hijack host cell metabolism.

Chlamydia trachomatis and Chlamydia muridarum spectinomycin resistant vectors and a transcriptional fluorescent reporter to monitor conversion from replicative to infectious bacteria.

Chlamydia trachomatis infections are the leading cause of sexually transmitted infections of bacterial origin. Lower genital tract infections are often asymptomatic, and therefore left untreated, leading to ascending infections that have long-term consequences on female reproductive health. Human pathology can be recapitulated in mice with the mouse adapted strain C.

The heterocyst regulatory protein HetP and its homologs modulate heterocyst commitment in sp. strain PCC 7120.

The commitment of differentiating cells to a specialized fate is fundamental to the correct assembly of tissues within a multicellular organism. Because commitment is often irreversible, entry into and progression through this phase of development must be tightly regulated. Under nitrogen-limiting conditions, the multicellular cyanobacterium sp.