NEW YORK (TheStreet) -- Shares of Petrobras (PBR) - Get Report are up 4.28% to $5.49 in late morning trading Friday, rebounding from yesterday's losses as oil prices turn positive on German Chancellor Angela Merkel's upbeat comments about Greece, according to Reuters.

The euro got a boost against the dollar after Merkel said that payments to Greece could begin if the country's list of reforms is approved, Reuters reports.

A weaker dollar makes oil more attractive, causing the rally in oil prices, Reuters noted.

WTI crude for April delivery was trading up 4.14% to $45.78 as of 11:09 a.m. ET today, while Brent crude for May delivery was also up 1.54% to $55.27 a barrel.

Oil prices declined yesterday after data showed the highest oil inventories in the U.S. in at least 80 years.

On Wednesday, Brazil's Federal Audits Court, the TCU, announced that it will investigate whether the board members of Petrobras mismanaged the company.

Also, Brazil's Comptroller-General Office will add six more construction and engineering firms in its investigation of contractors that were allegedly involved in corrupt dealings, bringing the total to 24 firms.

Brazil-based Petrobras is an integrated oil and gas company, engaged in the research, extraction, refining, processing, trade and transport of oil from wells, shale and other rocks.

Insight from TheStreet's Research Team

Tim Melvin commented on Petrobras in a recent post on RealMoney.com. Here is what Melvin had to say about the stock:

Before moving away from the Bain & Co. private equity report I want to share a few more investable observations I came away with after reading it this past weekend. Each year I have read the report I find it incredibly useful as a guide to opportunities in certain sectors and regions of the world, and this year is no different.

This year's report highlights Brazil and some of the opportunities that may be available in that troubled nation. I have held some Brazilian stocks for a couple of years now and it has been a bumpy, unpleasant journey so far. Over my holding period, we have gone from "this looks like maximum pessimism" to "maybe they will vote her out and jumpstart things" to "you have got to be kidding me." We have seen widespread corruption involving Petrobras, continued weakness in the economy and, just this weekend, protestors taking to the streets to demand the impeachment of the president the country just reelected. Brazil is a mess and it's not getting better anytime soon.

- Tim Melvin, 'Prospecting in 2 Troubled Economies' originally published 3/18/2015 on RealMoney.com.

Want more information like this from Tim Melvin BEFORE your stock moves? Learn more about RealMoney.com now.

Separately, TheStreet Ratings team rates PETROBRAS-PETROLEO BRASILIER as a Hold with a ratings score of C-. TheStreet Ratings Team has this to say about their recommendation:

"We rate PETROBRAS-PETROLEO BRASILIER (PBR) a HOLD. The primary factors that have impacted our rating are mixed, some indicating strength, some showing weaknesses, with little evidence to justify the expectation of either a positive or negative performance for this stock relative to most other stocks. The company's strengths can be seen in multiple areas, such as its revenue growth, largely solid financial position with reasonable debt levels by most measures and attractive valuation levels. However, as a counter to these strengths, we also find weaknesses including disappointing return on equity, weak operating cash flow and poor profit margins." You can view the full analysis from the report here: PBR Ratings Report