Structure and Binding Properties to Blood Co-Factors of the Least Sulfated Galactan Found in the Cell Wall of the Red Alga Botryocladia occidentalis

Three different populations of sulfated polysaccharides can be found in the cell wall of the red alga Botryocladia occidentalis. In a previous work, the structures of the two more sulfated polysaccharides were revised. In this work, NMR-based structural analysis was performed on the least sulfated polysaccharide and its chemically modified derivatives. Results have revealed the presence of both 4-linked α- and 3-linked β-galactose units having the following chemical features: more than half of the total galactose units are not sulfated, the α-units occur primarily as 3,6-anhydrogalactose units either 2-O-methylated or 2-O-sulfated, and the β-galactose units can be 4-O-sulfated or 2,4-O-disulfated. SPR-based results indicated weaker binding of the least sulfated galactan to thrombin, factor Xa, and antithrombin, but stronger binding to heparin cofactor II than unfractionated heparin. This report together with our previous publication completes the structural characterization of the three polysaccharides found in the cell wall of the red alga B. occidentalis and correlates the impact of their composing chemical groups with the levels of interaction with the blood co-factors.

A CLEAR CASE OF MRSA SEPSIS, OF AN UNEXPECTED ORIGIN

A 56-year-old man with a history of uncontrolled type 2 diabetes mellitus, benign prostatic hypertrophy and history of recent knee and elbow abscess presented to the emergency department with nausea, vomiting, and fevers. Two days prior, he presented to the ER and was diagnosed with acute presumed prostatitis and urinary retention. He was discharged on ciprofloxacin and an indwelling Foley catheter with urology follow-up. After being unable to tolerate oral medications, he presented again to the emergency department, at which time, he was febrile and tachycardic. Physical exam was benign except for a boggy and tender prostate and bilateral CVA tenderness. Labs demonstrated leukocytosis, elevated HbA1C, and pyuria on urinalysis. Urine cultures collected at the patient's earlier emergency department visit demonstrated no growth. Computed tomography indicated an enlarged prostate with patchy areas of low density. He was admitted with sepsis secondary to prostatitis. Blood cultures on day one showed gram-positive cocci , methicillin resistant staph aureus (MRSA isolate) and persistent bacteremia for three days despite therapy with vancomycin. After adequate dosing of vancomycin, sterilization of the blood was achieved, yet urine culture demonstrated growth of MRSA. Transthoracic rchocardiogram (TTE) showed no signs of endocarditis with good visualization of valves. He was successfully treated with 14 days of vancomycin.